Why bother with the cutting and welding of the wheels. The MGA crowd use 165 wide tires on the stock 15" steel wheels all day long. Recommended wheel width for the 165 is 4.0-5.5 so you should be good to go with the 4" stock wheels.
Re: the spark setup, there is a middle path. You could use the bike carbs as suggested and get a Megajolt ignition setup for about 170 bucks plus a toothed wheel and the pickup/coilpack/control module from a Ford EDIS-4 car. You won't have to worry about whether you got the right springs for your advance curve from a used disty. And you could tune the ignition as you see fit. Of course, you could set it up wrong too.
Several have used the Ford EDIS ignition setup, albeit with the MegaSquirt. But that should not matter. they worrk the same as far as ignition goes.
It is your build and you get to go with what you want.
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Chuck.
“Any suspension will work if you don’t let it.” - Colin Chapman
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