Well, first off, you have to realize what you are getting, once you have come to terms with that, its easy. They are good trucks, as long as you keep up with maintenace and realize that they are old and durable parts are gonna go bad, chances are, they will go bad when ya need it most. There are several things that I would replace right off the bat, ALL your relay switches, I think there are 17 of them, about 5 bucks each. The engines have been beat, never take them over 3000 rpm, just had the upper end done, and still keep it under 3. Oil pumps are another durable good that I would replace, under 50 bucks in parts, took an hour to change. I could go on and on. Remember, they have been beat and are still standing, just need a little love, be pro active with them and they will keep going. I bought a real P.O.S. in Clinton, Ill. Didn't find out til it was too late, check them out real good before you buy, these white washers put band-aids on everything.
If ya get one, and have issues, hit me up, I know them pretty well.
Simulators rule! Right fellow southern Ill victims!