Pressure building in tank

I'll look at the inside of my cap. I'm not sure how to pull off the line to the canister. The clip isn't adjustable or flexible. I've never seen a clip like it. I do not think these two issues are interrelated. Just brought them up at the same time. Sorry. I have not plugged the heat crossover in my performer intake. I've heard Eddy carbs are more prone to this issue. But swapping a carb right now isn't what I'm wanting to look into.

Kiss, how do you like that cool carb plate? I had been looking into them. Was gonna wrap my fuel line first with header wrap and go from there. Thanks for the conversations guys. I appreciate it.
The CoolCarb heat shield and spacer are fantastic but I wouldn't run them if I still had heat crossover. I talked to the owner and he advised against it. There are other spacers and heat shields out there.

Don't get me wrong I like Edelbrock carbs, I run one, but the fuel sits directly over the middle of the intake and with the aluminum carb body and today's gasoline it boils, easily. Anything you can do will help, such as wrapping the fuel lines and running spacers. Ideally you'd have a fuel return system at the carb to constantly feed in cooler gas, and with an electric pump. I didn't do that personally as it wasn't worth it to me and my limited driving.