I have an 83 early GT. It came with 7.5 and 4spd SROD stock. I purchased an 89 gt rear end swapped all the internals with an Eaton locker and 31 spline 5 lug axles. I'm not sure if i have to buy new hardware or anything to install it. I have summit upper and lower control arms, QA1 12 way adjustable shocks, weld in sub frame connectors. I just got out of the army an don't have very much wrench time. Is this swap something that i could do my self or would it be best to have a shop do the work. I just had a tremec T-5 cobra trans installed and changed the cam, intake and carb. Cylinder heads are my next venture.The rear end was just completed yesterday and waiting for good weather to install. Ive been on a tight budget and it has taken 6 years to get this far. My best 1/4 mile time at Fayettville, NC drag strip 12.74. I have seen 7.5 rear ends blow out before so that's why i am swapping it out before that happens to me. Thanks for the help.