I'm going to rebuild a T-5 for my SN95 GT with a 2.95 gear set. It's got 3.90 gears and I want to retain the rear gears but still get decent highway economy. The engine will have ported GT40p heads, ported Cobra lower, XE266 cam and Bassani mid-length headers & o/r x-pipe and Magnaflow cat-back. The 0.68 OD currently in it is too low so I'm considering the 0.63 or, if I retain the 0.68 fifth gear set from a 3.35 tranny, I'll have 0.59 with the 2.95 setup. Thoughts?