No Start Situation

A while ago my Blazer starting giving me trouble. By trouble, I mean that the truck would stall out when I hit the gas. The truck truck was not really driveable, as the throttle had to be (heavily) feathered to prevent it from stalling. I later chased this problem down to the oil pressure switch, which has been replaced. Now the truck won't start. I have air, I have proper fuel delivery, and I believe ignition to be problem. Trouble is, the truck has a fresh tune up (not even 20 miles on it, proper gapped plugs, new wires, newer rotor and cap, new module). I can't figure out what the issue is. I can't even get the truck fire with starting fluid. Help me before I have to junk it... :frown:

what year is it?

My bad, forgot that part.

1992 S10 4x4, 4.3 TBI (vin Z), 700R4 trans, 4 door, all options.