Money aside, I'd go for the G-Force T5 over the Tremec. Mike @ G-Force will make it exactly how you want it. You want specific ratios? Just ask!
Money an issue? I'd sell the new T5 and put it towards importing your own Tremec. It'd end up cheaper than the voerall cost of the modded T5, but a Tremec will never shift as nicely as the GF T5.
But then again, you can't break ANY gearbox until you've finished that car!!!
Get to it!