Ftylers right. If you're doing a swap anyway go for the OD. Then use 4.11-3.55 gears and you'll have grunt and cruising speed too. The 700R4 is a good unit & properly prepared can take the power of a hot street 350. Heck they were used in stock trucks with big engines for years.
If using the TH-375, check into it, because there was a 375 and 375B which are different internally.
good luck
chip
