Been there and done that! With success!
Turbo Coupes with Auto trans have 3.73 gears, and 3.55 gears when they have a manual trans. It's the same 8.8 rear end as in the 93 Cobra.
It takes 2 guys the first day to get the old rear end out and the new one bolted in place. It takes 1 guy another whole day to do the brakes.
You will need a several sets of fittings, I recommend that you get them from Matt90GT's website,
http://www.svo73mm.cjb.net/. Read Matt's instructions thoroughly, everything you need to know about the brakes is all there. You need to be patient and follow all the internal links, and there are many of them. You will need 2 fittings in the rear to adapt your old brake tubing to the TC disk brakes. The fittings go between the steel tube and the caliper brake hose. You will need another set of fittings to make a 2 port to 3 port adapter. To make life simpler, just buy the kits from Matt. You could piece them together, but it's not worth the time unless you work at an auto parts store with all the fittings ever made.
You need to drill the quad shock brackets 2” lower than the stock position on the TC rear end. The bolts are metric, so don’t loose them or the nuts. Use a 15/32” drill bit unless you have access to metric drill bits. I think the bolt is 12 mm , which is .472 inches.
See
http://www.hanlonmotorsports.com/for the speedo gear. With the Hanlon gear and stock tire size, my speedo is about 1 MPH high, which is excellent
You will need a proportioning valve, Summit has one for $40 + shipping.
You will need a kit (FMS makes the part) to gut the stock proportioning valve, Summit also has that, about $10.
You will need a new master cylinder, see Matt's site and make you choice. I used a 94-95 Mustang master cylinder. Note that rebuilt 94-95 Mustang master cylinders do not come with a reservoir. That means a trip to the junkyard and some more money spent. Your brake pedal may be very hard and almost impossible to lock up the brakes. I had to replace the front calipers with 73 mm calipers from a 91 Lincoln Mark 8 to get the braking performance up to par.
Bleeding the brakes will require 2 people and some coordinated effort. I don’t recommend using you wife or girlfriend to pump the pedal – they get offended when you yell at them. I used a homemade power brake bleeder constructed from a garden sprayer and some fittings from Home Depot. It cost about $25 and was worth every penny.
All in all I have been very pleased with the results.
