Have you put a fuel pressure gauge in the line at the carb? Just because you have gas doesn't mean you have flow/pressure. The gauges are pretty cheap...about $10. About 6-7 pounds is normal.
Are you sure the needle seat valve isn't sticking closed? The bowl fills up on start up and the valve sticks, engine runs out of gas and dies...
Before you take anything apart run the truck again and when it stalls grab the coil and see if it's HOT...If it's to hot to hold then it's bad.
Mike B
