Edelbrock carb overflowing with gas

[JMD]

Hey all,
Today was supposed to be the day when my 4 year project made it's maiden voyage, but the truck had other ideas. I have a reman Edelbrock 1411 sitting on top of a bone stock 454 with a stock mechanical fuel pump in my k10. The carb has worked flawlessly up until this point, and I've driven the truck a few miles around the block with zero issues. The last time I had then truck running was memorial day, and it ran great.

Fast forward to today, and the carb spews gas out of both vents. I figured there might be some varnish or crud where the needles seat, so I tore the carb apart and THOROUGHLY cleaned everything inside. No change, still runs for a second and then starts pouring gas out the top of the carb. Something is obviously allowing the fuel pump to keep dumping gas into the float bowls. I tore apart and cleaned the carb two more times and got the same result each time. Float bowls and needles look brand new at this point.

What else could the problem be? I can't imagine the float height got all out of wack just sitting there for a few weeks, and I never touched the fuel pump so it can't be too much fuel pressure causing the issue. Any help is greatly appreciated, I'm going nuts over here.