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Don't know exactly where the shock mount will be positioned. I think, closer to the wheel is better, but that creates a stronger angle, closer to the chassis is a better angle but is not as good for the bending load on the arm. Also, clearing the upper arm will help determine this.

Now it's time to tackle the upper arms. With my lower arm numbers set, I looked at other peoples numbers, Namely, Chet,Mark and Randy. They were using the Miata upright so I figured that would be a good place to start. They were kind enough to post their numbers as used in the Wishbone program. Problem was, they were not using the exact frame or the exact wheel size, so I did a little cyphering as Jethro says and kinda went from there. One was using a wheel one in lower than me so I added a half inch to the lower ball joint height. I came up with an upper arm lenght of 13.939 inches. That's close to 14inches. Good enough for Government Work.You know the old saying,"measure with a micrometer, mark with chalk, cut with an ax".
So I got my ax out and cut me some steel. Oh wait. I forgot, I made another of my famous jigs.

Similar to the other jig, except the spacing between the rod ends is 10 inches instead of 12 and the perpendicular length is about 14inches. So I draw my line down 14inches and drill a hole and put in a screw.

I also draw a second line and put in another screw, as seen in the photograph.

It just so happens that the upper ball joint we're using is a Moog part which has a hole in the center. This hole is where the grease fitting installs, but for now, we'll use it to position the ball joint.(tie rod end).. So we can put the rod ends on the bolts at the top and turn the ball joint over so the screw goes into the hole slightly and holds it in position. Measure the distance, figuring in the lock nuts and extended thread and -viola- you have your length of tube. Works great, but there may be a problem.With a rigid upper control arm, as you extend the rod ends out for adjustment, the distance between them gets greater(unless you're using bent arms). This could mean that your arms no longer fit the chassis brackets. What to do? Well, Kinetic sells an upper control arm which is not fixed, but has the two legs of the arm movable. Sounds like a winner to me. So just build the two arms so that there is a joint between them. Look at Kinetic's site. Another thing to consider is caster. How much adjustment do I need and how much adjustment will the arm give me. This is what the second line and screw on the jig is for.If the arm is built symetrical, then you have no caster built in, and will have to depend on adjusting the rod ends to achieve caster. After being on this forum I learned that a lot of cars were running 7 or 8 degrees and some were running 10 or more degrees, so I figured the safe thing to do was build the arm with some caster even when the rod ends were in their neutral settings. With my uprights, I figured that with the top ball joint one inch behind the lower ball joint(when looking down from the top), or stated another way, when the top ball is one inch closer to the rear of the car, that would give me about 7 degrees of caster. Any more caster or any less would be made by adjusting the rod ends. That is what the second line and bolt is for. It is one inch over from the center line, therey moving the ball in that direction. But with this design, I don't have to make left and right handed arms, they are interchangeable. The arms you see here are not the real version, but are only mock-ups so I can put them on the car and try them out. THe demensions are correct thouth. Note the modified carriage bolt, and the nuts acting as bungs(there's that word again).

Now it's time to put the arms on the frame, but first I have to attach the brackets.Put the car on the build table and got her all lined up. The lower brackets were no problem. Just measured up from the table the correct amount. Using Kinetic's angle brackets on the front, I followed his suggestion and put the rod end and two spacers between the two sides and installed the bolt and nut. One thing you should be a little careful about. When you clamp the two piece bracket to the tube, make sure they don't twist slightly which will make the bolt hard to install, so I clamped and loosened the nut slightly to check for free movement on the bolt. Not really a problem, but for someone who isn't used to such things, you wouldn't want to weld the bracket halves on and then find out you couldn't easily remove the bold without damaging the threads. Anyway, insstalled the front bracket and just measured back parallel to centerline 12 inches and tacked the back one. Same for the other side. Now for the uppers. Same thing at the front, Measure up from table and tack. The rear one was a little more of a problem. Since the vertical tube was not yet installed I had to first determine where it would have to go. As it turned out, when I determined the position of the upper bracket, the FU tube(now I understand why it's named that) interferred with the lower bracket. Well no problem I thought, just move the bottom over and angle it. No.Tried that. No go. The bottom frame rail goes back at an angle, so when you move the lower part of FU back it also move it out therby making the bracket move out from centerline. I had made a little device to help determine where the bracket had to be and to later check the position. I made this little device. I simple put the stick inside the front bracket and marked the hole, then I drilled the hole thru the stick. Next I put a bracket on the stick. This will get me clost to where the bracket has to be at the rear as shown here.Since I didn't know the exact angle the bracket had to be, in either direction, I could tighten the bolt just slightly and swivel the bracket up or down and twist the stick front to back with the back of the bracket against the FU tube. Otherwise, it would take about 3 or 4 hands to hold everything. Once I was pretty close, I clamped the FU tube in place and then tacked the bracket. I wasn't real satisfied about my positioning, so I made another little device to check things. I just laid the bottom and top piece on a table and tacked the upright, to keep the top and bottom parallel.This way I could use the bottom on a parallel line on the table. Drilled holes in the top 10 inches apart for the bolts. Moved it to the front bracket, inserted bolt in bracket and bolt in device and ran small bolt up to bottom of bracket bolt. Did other end the same. Put square on end of table to match front of device so the device is parallel to centerline of car.

Here's where the bottom of the FU-1 tube attaches. and a couple of other views

Control arms are on, at least for now.

Now on to something else. You may have noticed, I don't continue in the same direction all the time. Since I don't exactly have a timetable for this project, I like to work on whatever I feel like at the time, but still trying to make progress. I've been thinking about the gas tank. Even though we're a long way from needing gas I still need to figure that out. A lot of guys just buy a tank and put it in the trunk, but that pretty well eliminates the trunk.So I make a mock-up out of masonite. My goal was to have at least a ten gallon tank(if I still lived in Texas, I might have a hat that size), and still have a small trunk. This tank will sit just behind the rear bulkhead and will hold a little more than ten gallons. I'm not too sure about this tank, so I have been doing more thinking and I've come up with a solution. Two tanks. Yep, you heard me. I once owned a Lotus Europa which had two tanks.Here is my Idea.
This is the left tank mock-up. It will sit at the extreme left rear of the car. Another one on the other side. Filler will be just above the tank at the rear corner. Will work great, but will require more effort to fill two tanks, even with a balance tube between them.

Even though my double gas tank system will work and will leave the most trunk space, I've decided to go with a single tank after all. Here is my latest(and I hope my last) tank idea.
This tank will fit just behind the subframe and differential. The top of the tank is wide enough for the filler and fittings etc, and this tank will hold a little over 11 gals. Also, it can be built with just 3 pieces of aluminum , one piece for the main body and a piece one each end, plus a couple of baffles inside.

Here is my build table at the front bulkhead. Why do I have a washer under the frame?

I discovered that if I raise the frame just slightly I could slide a ruler or other device such as a square under the frame, making it much easier to measure things and keep things square.

Did you verify that the tie rods clear the front tube of the lower A arm throughout the travel range of both?
From here at my desk you seem to be having the same problem that almost every builder that used miata uprights had to figure out.

Moti

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Moti

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Will the rear lower control arm bind at droop.
It looks like it will in the pics.

Not yet, that's next to do. I'm hoping my better looking arm will work, if not, my other one will, I think. I haven't determined the inner tie rod pivot yet. That's why I mocked up the upper arm, so I could go ahead and check this. We'll see.

I don't have any interference with the lower arm. The bracket is right at the edge of the tube. Moving the bracket any farther to the rear of the car would make it move inward from the edge, so it's at it's most rearward position and still be at the edge. After you asked, it got me to thinking that maybe I had missed something, so I did a double check just now. Here are two photographs. the first at about 5 inches and the second at about 7.

Thanks for asking questions guys. Maybe it'll keep me from making any major mistakes.

Since you asked. Previously, I had considered making the front tube perpendicular to the chassis and the rear tube mounting farther back like this. That would have solved the problem, but I wasn't sure what that would do, strength wise to the arm. I even considered mounting the rack in front of the front bulkhead so I could keep the same front arm mount on the tube, but I decided that the rack needed to be behind. We shall see.