just do it, 1st 5 things i would do:

1) make sure its running in tip top shape, change all fluids,belts, tune up, shit like that

2) add more steering angle. this shold be pretty easy cause i have an 81 celica with the same basic steering and added a shit ton more angle just by removing the steering stops. one down side is that you have like a zillion turns lock to lock, so you will be busy as shit behind the wheel unless you put in a steering quickener.

3) lower the truck and get really good shocks, perferably adjustable

4) get an lsd, i would say weld it, but since you have a toyota truck everyone makes an aftermarket locker for the rear end for offroading. they are cheap and should last forever.

5) make sure you have a good clutch and good radiator. the cooling system and the clutch take a beating, so make sure they are in good shape. the 5spd w58's are everywhere and cheap, so i would swap one of those in.