where to find 9" rear?

I've talked to a bunch of guys that bracket race fox bodies and they all say to go with skinnie kid race cars 9". But at their web site they only have them for fox's. Does anyone make them for 99+ GT's? Also, could I bolt up the stock brakes, and the suspention I already have? I would be pissed if I couldn't bolt my UPR control arms back on. I want to go 9" for my future plans, and wild rides race cars anti-roll weld in system. And when I find a 9" what are the chances someone would want to buy a used 8.8" assembly, with 31 spline strange axles, FRPP 4.10's, and ECTED differential?
Thanks~Tony

I'm hoping for 900hp next spring, plus I want a spool and 35 splines. Also changing gear ratios takes about 4-5 min. with the 9" so I can experiment at the track.

I'm going to do a built 4v block TT and N2O, strip only car.