I'm not 100% sure on this but its my understanding that the original gear ratio doesn't affect the carrier. The difference comes when you have the TRD package and the E-locker. I'm pretty sure that all non-TRD Taco's have the same carrier and all the TRD Taco's have a different carrier. I don't think factory gears determine the carrier.
Good luck,
Sam <img src="/forums/images/graemlins/cheers.gif" alt="" />