I have a 1987 V10 Silverado with a 350 V8 and i have been having problems with the engine cutting out and stalling so i took it to a garage and they checked the wires and they needed changed so i changed the plugs, wires, cap, and rotor, and the problem got worse now i think its running on 6 or 7 cylinders and the lights and radio cut out and flicker help me out somehow please

 

Check your engine to ground wire, they have a tendency to get against the headers and burn through. And they are very thin.Ttry adding a heavy ground cable at another point and see if it helps, Napa has wide ones for just a few bucks.

 

also check your timing, it could be off and thats why it got worse.

 

do you have points in your C10?