If you have removed all of the emissions stuff but are still running the stock carb, that's the wrong way to go about it.
The stock carb HAS TO HAVE all the emission junk to operate the way it was designed to do.......that said, I don't think that is the biggest problem you have here.....I would pull the bed off and have a look inside your gas tank......you may have some problems in there if the truck sat for a while at anytime in it's life.
Here is what a rusty tank looks like, and what will find it's way into the carb! BTW, this is all from the same truck.
Float bowl on the stock carb.
After the "gas" evaporated.