If you want to go cheap for running muddy trails this was my set up in 88-89 and I had a blast in Northern New York and Pennsylvania in the muddy summers and snowy winters:

3" Bodylift, 34 X 9.50 TSL's on stock rims and a rear detroit locker. You could get a lockrite now and go even cheaper.

I added a 4" Suspension lift nd went to 36X12.50's the next year and looking back I think the initial setup worked better all around.