rough idle 95 k 1500

I have a 1995 k1500 305 tbi that has a rough idle.

I changed plugs, plug wires, dist cap, and rotor. No improvement. The plugs I replaced were only in for about 3k miles. They had a fair amount of black carbon build up.
Not sure where to go from here. Thoughts?

Have you tried doing a manifold vacuum test, compression test, fuel pressure test ? Do a "fuel pressure test" search on the Chevy forum. "OldMaster" has the procedure.
Have you checked for spark, bright blue/white, at each of the plugs ?

Have you tried test the pick-up coil ?

Just some thoughts.

These are bad for carbon build up on the injector bodies and tips. You can clean up alot of the stumble <provided there is no intake leak> by using throttle body cleaner in and around the TB. Also get the fuel system pressure cleaned to clean carbon from the injectors. Should clear it up.