are you switching from the stock 2.73? if you dont have tlok, get that while your at it. and get at least 3.73 gears. I recommend doing it yourself. Install will be well over 500.00. Just get the gears and tlok and some friction modifier and go to town. its really not that hard. If you need me to, I can post a link to an article that I wrote on doing it. This is several years ago, but its around here somewhere. Its not that hard of a job though.