I just noticed this. The Domes have a 1 and 2 inside on the roof that match the piston's 1 and 2.

Not sure if it happens for all years but it does on these 4 screws.

Interesting.....Is the 1 the front and the 2 the rear?

I missed that much tracking but I will look on the carb bodies for numbers. Funny thing is that the fuel bowl tops have a 1 and 2 so it may trace from there.