1993 4.3 v-6 Wcode Chevy. Starter gear sometimes will not engage with the flexplate. When starting it only clicks for several tries then it will go ahead and engage. I have replaced starter, battery, battery cables, ignition switch, and shimmed starter every way possible. Don't know what's going on.
I'd have to check the actual voltage reading at the starter soloenoid. Check grounds. You could use a remote starter button, maybe the leads are long enough to get you out from under the vehicle. You have to make sure the tranny is in park or neutral and a functional e-brake is set. If your under the vehicle, vehicle in gear, and you accidently start it, it will run over you and anything else in the way.