eating starters, want crank with switch read more

My dad gave me a 1988 silverado 3500 dually, that someone did not fix correctly. The truck wound not crank thru the switch, so they rerouted it (jimmy rigged). the dash lights and stuff comes on with the switch, but they have put a toggle switch in that you have to flip to crank the truck. I think this is eating up my starters, because we are on our second one. this one has worked fine for over a month, but now has gone back to a real rough grinding noise. Is there something on the bottom of the steering column that controls this where I can fix it back right, and save myself the trouble of putting on another starter.