Help Jimmy will not start!

Make: GMC1990 Jimmy 4.3L V6 ( vin code:Z)
Milage 200,000 plus

We got a jimmy and drove it for about 2 weeks. The Jimmy stalled while driving. We changed the fuel pump and filter; changed spark plugs and wires;changed distributor cap, module, and rotor; changed the igntion coil and ESC module; changed battery and cables; changed some melted fuses, There is still no spark, apparently there is still power in the ignition area. We were told the distributor rotor does not turn, no movement at all. What can be the problem, can you help us. We spent lots of money on the parts and time. Thank you. Tonya