I found some really old pics of your wiring here:
http://locostusa.com/forums/viewtopic.p ... &start=150I’d move all the grounds to the top rail with a 1/8x1x1 or 2 inch strip, within a foot of four or more components, pre-drilled, vertical and welded on two sides. I use ¼-20 bolts bolted to the tab, then a washer, eyes, washer, lock washer, nut. I think they are 1-1/4 long.
Another, cleaner option is to drill a hole in the center of the tube, weld a nut over the hole, chase the threads, then bolt the grounds to the rail directly. Then you will never stab yourself on protruding threads and the bolt is less likely to corrode inside the top rail.
For the relays, when you weld a strip to mount them, make it a couple inches longer to provide a ground stud on the end and a small hole to zip tie the loom.
I’d move the engine ground to within a foot of where it attaches near the engine mount, then weld a tab to the frame side of the engine mount to bolt it on and solder the ends.
Wiring, including grounds, should be above any liquids that can soak them and soften the insulation or corrode the wire.
Ground tabs should be easily accessible for tools and cleaning but not draw blood on the mech trying to work on something else.
It is better to have a single purpose ground attachment versus also holding a bracket to the vehicle so they don’t get disturbed/flexed from unrelated service. It makes sense for retrofit but not a preferred practice.
The chassis is a negative bus bar. Ground points should be close to the component to reduce volt drop, wiring, cleaner install, and less weight.
The battery cables look to thin for this application. They should be in a gauge appropriate to the cca requirements for the donor vehicle. I’d go 4-6ga with short cables for a miata drivetrain. It looks like you have a 6ga for the engine ground to chassis but the bat cables look really thin in the pics of when it was not finished. I crimp in a vice and solder the eyes then heat shrink. When buying cable, beware “copper plated” in the fine print.
My sunroof has been leaking on the 4.3l fiero. Rotted my Mr. Mikes leather seats
but they are about 20 years old now. Another forever project I need to get back to. I never should have retrofit a sunroof roof.
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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS
viewtopic.php?f=5&t=13225&p=134742Simple Spring select
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360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12