Rear end question

Can anyone tell me what rear and gears should have come with on a 71 Scamp born with a 318 and 904 trans? The guy I bought it from a year ago said it was a 8-3/4 with 3:23 gears. The engine was changed and actually is a 360 which was supposedly "fresh", not true since I just had it rebuilt. Also I'm questioning the 3000 RPM stall converter, I probably should have changed the converter when the engine was pulled.

The bottom line is the trans is leaking pretty bad from several areas and has been to two shops Doesn't have the correct dip stick, so I'm not sure about the fluid Level. The trans is really the only real problem left short of whats going on with the rear. Stupid question but if I do change the trans going to a 727 probably wouldn't make much sense?

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