2:30am EST, something does come to mind, but not really from the pictures per se.
Under the external gas cap, is there a secondary cap underneath?
If so, it should be a vented cap.
If uncertain if you have a vented, or non vented cap, or whether the cap, if found to be a vented unit, is suspect, I purchase an appropriate replacement vented cap and see if that solves the problem.
In addition, while picture 115 clearly shows a billet fuel filter, I'd check to see if the filter inside is clogged.
Picture 123 shows an electric fuel pump, but no fuel pressure regulator, I'd be replacing the pump and adding a regulator after the pump, and a fuel filter before the pump as well.
Finally, picture 114 shows multiple carb spacers, the bottom 1-1.5" may have been required due to the Edelbrock carb currently in place, but the upper "phenolic" spacer needs to be removed and replaced with a simple 1/8" heat shield (just 1) from the
MrGasket "3170" kit.
I've been using them on all my big block, and small block powered cars for years without an issue.
If not used for clearance issues, I'd remove both spacers and just use the 1/8" heat shield in their place.
Bill S.