Just as a note though, pretty much any transmission shop will do gears, performance shops just charge more to "do it right." Gears are really simple actually its just a matter of knowing what youre doing, so just take it to any tranny shop, and they should be able to do it.
Black with saddle 1996 Mustang GT convertible. Manual. NPI, 2v 4.6L. Full bolt-ons.