After it dies at stop light, does it start right up?
How can it idle fine and not idle fine when stopping? So when does it "idle fine" ?
It seems like debris is moving forward as forward momentum stops, then floats back on acceleration. Fuel filter, tank pick up or tank debris? If it runs good in all other modes like you say. Idle, acceleration, it doesn't seem like carb or pump?
Not flooding right?
Plenty of gas in tank right?
I know this sounds silly but can you go from 30MPH to a gradual roll and let truck stop without brakes or trans and see what is does. In a large parking lot or something.