Engine Rough Idle starts about 5 seconds after coming to a stop?

I have a 1991 c1500 I've changed the plugs, wires, distributer cap, button, iac valve, tps, cleaned the throttle body with crc and new gaskets, pcv, and cleaned the egr valve. It shuts off 60 % of the time when it idles down the timing was set with a light. It started when it started running hot. I replaced the water pump, radiator, t stat that's perfect now but the truck still idles kinda bad and shuts off, runs perfect on the highway. Please help

I replaced the iac, I've searched for vacuum leaks 1000 times and can't find anything. I sprayed starting fluid around the intake to see if it was sucking air, but the engine never changed so I ruled that out, is their a better way to check?

1989 Chevy C1500 2wd 350eng w/132203miles
The problem is the truck sputters severly when cold and also for a minutes on warm starts.
When started, the motor surges greatly, once in gear, it surges to the point of almost cutting off. Once the gas is pressed, it will act as if its bogging down then it pick up then bog again. If I press the pedal about 3/4 ways it launches with a slight miss. As the engine heats up the problem slowly fades to just being a little hesitant at highway speeds.
Parts replaced: plugs, wires, egr valve, throttle position sensor and gas treatment.

Engine has a somewhat rough idle. Not terrible, yet noticeable. Have replaced all visible vacuum lines with great improvement. Still a little bit of a miss at idle. Truck will run great on acceleration. Maybe EGR valve issue? New plugs/wires also. Pretty much have done the works on this truck and it still persists to idle with a miss.

Any information you may have, thank you in advance!

Okay thanks for the information. I just replaced fuel pump due to failure 300-400 miles ago.

Have not done cap & rotor. Not sure on the timing also. How would I go about checking the timing?