Needs throttle or choke

Where did you spray WD40 to test for leaks? This test is not 100% valid unless you sprayed it on all sort of intake system locations. And, you seem to have a pretty large leak. A vaccum leak could come in from anywhere in the intake system. Again, put a vacuum guage on it and see what you have.

BTW, do you have power brakes? If so, remove the vaccum line to the booster and plug it and try. Plug any vaccum line to the trannie too.

Have you set the idle speed screw up to see if it will idle at at, say, 1500 rpm without any help? Then recheck your fuel pressure and let everyone know what you have on that and the vacuum. We're all shooting in the dark without some definitive tests and data.

Changing the carbs 2x is very likely to have eliminated the possibility of a plugged idle passage in the 1st carb, which was my other thought.

Battery sounds OK. I owuld keep it on the charger as much as you can.