Power should go from the ignition switch > clutch switch > fender solenoid > starter all in series. Sorry I haven't been back for a bit to chime in on this. Simple electrical theory. Put stuff in series and if it all is good you have a circuit. Break the circuit any where in that point (bad part, bad wire, ect) and you no longer have an operating circuit.
Here is a scan from the Ford electrical and vacuum troubleshooting manual factory service manual for my 94 (not sure how much would be different since your 96 should be OBDII)
Actually, use this diagram, I whited out automatic trans stuff...
This diagram shows when you turn your key to "Start" battery voltage should go from the Red with Light Blue wire from the ignition switch into the clutch switch, out by way of the Pink wire which splices with the Red with Light Blue wire that goes to the fender mounted starter relay. To check voltage on these wires, ground the black lead of your meter and probe the back of the sockets with the red. I hope this helps. Oh, and btw, as far as my manual goes, ebay FTW and ALWAYS make sure your truck is in neutral before jumping the fender mounted relay or the solenoid on the starter itself. I also broke my fender mounted relay jump starting it with the tire iron I used to beat my starter with, then broke the new one so I have to take it back. I would suggest using a 1/4 drive ratchet to install a new one since you can't torque the snot out of them causing the new relay to break.