Yes, you are correct about the fuel lines and accelerator pumps.
But, I’m not sure what his linkage looks like. What I have, I believe it’s the factory setup, not 100% sure. Is adjustable so you can have the outboard carbs come in when you want/need them. Also the outboard carbs on mechanical setups do not have mixture screws like the vacuum carbs do. Only the center carb. It has a metering block with the mixture screws.
If it didn’t vapor lock before the six pack was installed, I would think it would be something in the change to cause it if in fact it is a true vapor lock.
Op, are you sure all carb adjustments are correct? Floats, jets ect?
There are some great threads on FBBO about six pack tuning. Very lengthy reads but worth every minute.
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