i have an 89 lx that has a built 8.8 (auburn 31 spline posi auburn spool 4.10 gears 31 spline superior axles. if i take the whole rear end out will it bolt up to my sn ? if not can it with some work ? and can i use the uppers and lowers off of the fox for the sn ? please help
Yes. The rear ends are the same from '86-'98. Just reuse your SN95 axles and brakes, as the Fox axles are too short. I am not sure on the control arms, but I would think they would work.
Yes, as 9 Deuce GT said, the housings are exactly the same, as are the control arms. But since you have 31 spline axles, you would either need to get new 31 spline 94-98 SN95 axles to keep the disc brakes as they are on the 95, or run the stock Fox drum brakes, or get the www.NorthRacecars.com brackets that let you use the SN95 calipers on Fox axles. Or if you want to, you can cut and install the SN95 brake brackets inside the axle flange and move the calipers in to match the Fox axles. The info is here: http://www.corral.net/forums/showthread.php?s=&postid=3123067#post3123067
Lots of options, just need to decide which route is best for your wheels and tires.
The overall length is shorter from splines all the way to the flange for the lugs. Imagine standing the axles straight up on their lugs. If both the Fox axle and the SN95 axle were standing next to each other, the Fox axle would be 3/4" shorter. Some say the SN95 axle is longer to accomodate the exciter rings for the ABS system on '94+ Mustangs.