Just a tidbit of information concerning the list on page 1...
It lists that it was the Mustang GT that had the turbo that is incorrect. Mustang GT's have ALWAYS had V8's. The turbo mustangs were called SVO's and shared the funky bi-level wing of the merkurs.
GT (notice the normal little lip on the back):
Mustang SVO, bi-level wing (also has a hood scoop):
If you're looking for the T3 with the .60 A/R turbine housing, you can find them on the following cars:
'84 - '86 T-Bird Turbocoupe (manual trans, I believe auto as well)
'85-'89 Merkur XR4Ti (MANUAL ONLY, the Auto had a .48 A/R turbine housing)
ANY Mustang SVO.
You'd never guess I used to have two Merkur XR4Ti's, one of which had a mustang T5 tranny swap, custom intercooler setup utilizing a saab radiator and an ebay I/C, larger SVO vane air meter, and a big fat turbonetics T3/T4
I happen to have a couple of these Merkur turbos laying around... If I'm ever able to free up some dough, that's the one that'll end up on the Miata.