1989 Shelby Dakota
 

Truck only starts part of the time. Turn key and nothing happens not even a click. Battery is new and test good. I can start multiple times let it run turn off and no restart. After sitting a good while will restart. Turn headlights on and turn the key and lights do not dim. Starter? Truck has been sitting in storage for awhile. Any input would be greatly appreciated.

Check out all of the wires going to the stater, lose corrosion etc, try bypassing the starter solenoid and see if it cranks.

Yeah, check the cables, a lot of the time it's them that is the culprit. Check for loose connections to the battery, any corrosion/fuzz, check the solenoid out if external and maybe try bypassing it temporarily if everything else looks good.

EDITED: I see now I just said exactly what iowan did. sorry :D. Carry on.