Take the small wire off the starter(the solenoid wire) Put your volt meter on Vdc...black to ground somewhere on the truck and the red lead on that wire. Put your clutch in to see if there is a signal(12V) to the starter. If there is a signal then the solenoid is bad.
If there is no signal. Then you have to find the starting/interlock relay under the dash. Pull that out and test it. I should show you on the relay how the contact are wired up. 2 for the coil and 2 for the N.O. contacts. Put 12V on the Coil side and test for continuity with an OHM meter. If that tests ok then your clutch switch is bad.
If you can get at the clutch switch. Pull the wire off of that and put an ohm meter between the contact and ground. Operate the pedal and check for continuity to ground. There should be 0ohms. If there are two wires on the switch then put the meter between both of the contacts on the switch and test for continuity that way.
This doesn't have to be done in this order....