so I have an 88 4cyl that has been converted to a 5.0 and I was wondering If I should stick with the 7.5 rearend or I have an opportunity to buy an 8.8 for $150 that is out of an 86 with stock gears and everything. If I stick with the 7.5 what should I do to it because it doesnt have posi. and If I should get the 8.8, what should I do to that before I put it in the car? Thanks