I agree w/ aliaZ, I replaced my clutch a while ago and addressed a rear main leak and discovered it was not the rear main but the rubber seal between the retainer and the oil pan. I bought the rear seal kit from Z1 and haven't experienced a leak yet. Unfortunately, it sounds like you may need to drop the tranny again to take care of that leak. It is crucial you hire someone w/ Z32 experience to properly diagnose and fix our cars, good luck.