I want to tune up my durango what can I do?

I own a 2002 Dodge Durango 4WD with the V8 4.7. The front end has been very bad lately. Both the half shafts and the rack and pinion are bad. The transmission pan has a broken bolt so it is getting flushed and resealed as well as filter and all the goodys. This is all getting fixed in about a month and after wards I want to give the car a tune up. It has 162k miles but runs strong and has had regular maintenance. I bought it used from a propane company that used it. It actually had a CB radio in it and a propane tank it was crazy before I bought it.They showed me Doentation of all the work and I don't think the engine is the original because it just runs to good. I am going to do rotars in the front as well as pads. I did the drums and shoes about six months ago. What else can I do to really tune up the vehicle with power and performance? I know the basic plugs, wires, oil change, air filter, and maybe coil packs but what can I do to prolong its inevitable death? I probably will spend up to 600-800 on a tune up and will do all the work myself.