I just installed rear disc brakes from a 96 v6 mustang on my 88 gt. Everything fits well except the soft lines from the calipers to my hard lines are way too long is their any other ones I can use from a different year mustang that maybe shorter that will bolt to my calipers.
You need softlines from a 94-95 Mustang. They are different and bolt to the axle. 96+ bolt to the body. You don't want these.
Bolt the 94-95 lines to the axle and form a loop with the stock brake line. You'll then need adapters. I think it's 3/16 female (or 3/8") to 7/16" male. If you go to autozone, they are in the aisle with the brass brake line adapters in yellow packages