no T3 on 87-88's
I like the sound of that project, but I hate to inform you of a mistake. There were no Garrett T3 turbo's on the 87-88 Turbocoupes. In 87 Ford switched to a Borg Warner IHI turbo with an intercooler, which had a smaller turbine housing, for faster spool up, but a lower flow rate. The car boosts hard from about 2G, but by the time you hit 4500, the turbo is choking the motor, and accelleration starts to die off.
The T3's were available on 83-86 Turbocoupes, SVO Mustangs, and Turbo Futura's. They took longer to spool, but kept pulling hard until redline when they did come to life. These cars didn't have intercoolers, (except SVO's) so their power output was slightly lower, even with the bigger turbo.
As for your question, though, I'm lucky enough to not have had the chance to pull my turbo out of the car for rebuild, yet. (and I stress yet) If you need more info, try turbotbird.com or NAT
rg (North American Turbocoupe Organization). Also, the boys at turboford.org will most likely be able to help you through every step of the process.