Hum. My car is a '73, #4066. I have the pedal plate space out 1-1/2" (2 layers of birch plywood) and have Halls "polished aluminum" master cylinder on there. It uses an adapter.
It does not hit the trunk lid at all.
I have not clayed it to see how much clearance there is.
I don't know why mine clears and yours does not? Maybe just the height of the master from the center line up?
IF you change things on these cars to an "update", it isn't a bad idea to deal with someone who is really just a basic hot rodder to boot and understands if you are going to mess with them, make sure that the substitute part works.
Did you contact Kirk Evans on this? He was the one that "completed" those cars as Amerisport to begin with. I'd start with him.
You probably need to call him directly. He is only on here sporadically.
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