I live in a very hilly section of the California foothills. I bought a truck with 33s and 4.88s. It was great in the hills. I rarely had to drop below 4th gear and the truck felt pretty sporty. I then went with 35s and kept the 4.88s. This was OK but I spent a lot of time in third and my milage suffered. On ground that was more level it was fine. Now I have a 35s and 5.29s and it is better in the hills and fine on flat ground but not as good as the 33s and 4.88s. I agree don't do the gear change until you have the axles you want. I will say that my IFS has worked great for all kinds of wheeling including slab crawling in the sierras, snow running, and mud runs. The solid axle is really only going to help you on the hardest .01% of runs if you have locking diffs. Good luck!
