I'm a mini truck guy, but here is what I think.
First swap the trans to a SM420, or SM465. This will get you a low 1st gear, and still keep the 1:1 3rd gear that you have now. this will help you crawl.
If you do this you will need an adapter for the T case, so you may want to concider a dual case at the same time.
I run steel wheels on rocks. They will get hit and scratched and dented. So steel is cheeper. I also run 10" for the wider track. Not sure whet offset you should run since I got a mini. But you may need to trim the fender for turning.
