nvycrmn, first off, based on the rig that you are starting with, time in the tranny is going to be a must to make something that is going to last through the pulls if you up the power any. Going with say a stage 2 tranny kit will help firm up the shift points and help the tranny just simply stay together better. The components are strong enough, just the programming blows as it is designed for a smooth ride which is contrary to longevity of the tranny under heavy loads.
As for upping the overall power, I would tell you to do some looking for a whipple supercharger (NOT a centrifugal supercharger). These can be found on some lightnings. I say this because the whipple is going to give you more power over the whole RPM band vice the centrifigul supercharger giving you tons of power gain up high, but little down low. If you were focusing on only pulls, then I would tell you to go with a twin screw setup. But, the whipple is going to be very good for the 4x4ing. Think about it, how often do you have the engine up over 4,000 RPM when out in the woods? How often at 2,000 or so? You need a supercharger that makes the most power where the engine is going to be working at most of the time.
Doing the supercharger bit, it should make for a cheaper overall build as you don't need to be buying a whole new motor and working to make the new motor work. Add in some long tube headers, some cut outs downstream of the cats and you can really make the expy into a monster.
