Starter doesn't spin, no power to bottom 5 amp fuse

Hi, My older K5 full size diesel blazer has a problem with the starting system. Solenoid doesn't click to initiate the starter, and the bottom fuse (5 amp) ignition? Doesn't have power to either side, and with the key on, no power to the neutral safety switch at the bottom of the steering column. I've replaced the ignition switch, and cleaned the terminals at the (center) of the firewall. Last time I replaced the starter with a Bosch re-manufactured unit, I installed an extra wire to the starter to bypass the ignition switch (for testing purposes only), and when I touch it to the battery, the starter engages, and spins. I tested the fuse links that go to and from the starter and they have 12 volts at each end. The pink wire from the ignition going to the starter, but tested at the firewall bulkhead connector doesn't send power with the ignition in the start position. With the key in the run position, the radio, and dash lights work. The dome, and headlights work as they should. Do you have a wiring diagram for the starting system so I can locate where the power should be coming from to the fuse, and starter? Thank You all!