I have pulled the carb twice now for the same problem. Each time after I have drove the truck and shut it off, the next day I come out to find a puddle of gas on the intake under the accelerator pump and the other side of the intake where the gas has run over I guess. I have seen it drip out from the pump while it was running through the (plunger?) and fill up around the gasket of the pump. I know I put the pump on right the second time with the gasket, so I dont know what else could be causing this. Have any of you ever run into this kind of thing before, and if so any advice would be much appreciated.

 

I'll try to explain this, hope you can understand. It would be easy to show you but may be hard to put into words.
Take the accelerator pump off again.
use a straightedge to check the side of the cover( the side with the arm that pivots)
they are usually not straight so it will not seal the gasket properly.

This is real common on these and holleys.

Take the cover and place on a flat surface.
now comes the hard part, take a small hammer and tap on top of the pump arm right over the pivot pin. DON'T hit to hard or you can break it. Keep checking it for straight.
Sometimes you have to raise the corners of that side and tap so it will go straight. I usually straddle a small opening on my vise and tap. Good luck. Moose

 

Where could I just buy a new plate?

 

I've never tried to buy just a accelerator pump plate. Not even sure where to begin looking. JunkYard??? If you have something else to drive. Pull it off and send to me and I will straighten and send back to you. Or I could se if I have another carb and send you one to install and then you could send one back. But you need to check with straightedge and see if warped, and not a crack in the housing somewhere. If I can help PM me and I will see what I can do. I have some old carbs, not sure if I have many two barrels though. Bruce