Hi all. I am running 3.5" of lift on my 07 with 35" tires and I would like to switch to 4.88 gears. My question is; where is a reputable place to get something like that done (I live in S.W. lower Michigan and there are a million mom and pop garages)? Can I do it myself? If so, how difficult is it? Where is a good place to buy them?