If memory serves these 40+ years, the VW ring and pinion in the old air-cooled bugs and buses, The differential/ring gear subassembly could be installed with the ring to the right or left of the pinion gear to change direction. Ths was to accommodate the outboard reduction gears on the pre-1968 buses which gave a steeper gear but reversed rotation. If the transaxle was for a bus, the ring went on one side, for bugs, on the other side. I had a shop rebuild one for my old bus, but it was done for a Bug by mistake, then they hung the reduction gears on it. I got it home, put it in, and had one gear forward and four in reverse, but I could back up really fast. Pretty scary in a bus. The shop just had to flip the gears to fix it, but I had to do removal and replacement again. Not a fun job even doing it once.
Once in a while you might see a super-lowered old VW bus: they took out the reduction gearboxes, which drops it
down about 9".
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Filliam H. Muffman
I would need more info on if the transaxle was reversed, or if they got a revised camshaft to reverse the direction the engine turned. If the engine turns the normal way, the VW transaxle wasn't meant to be driven that way. " HOWEVER, you are turning the drive gears (1-4) the opposite way that they are designed. The ring and pinion gear is striaght cut - no issue there. The drive gears are helical cut - meaning the helix or pitch of the gears causes them to be pulled together as power is applied. This is good for strength. When you turn these gears in reverse, the helix is pulling them APART. This is bad, say at 5000 RPM on an AutoX course when you are trying to change gears."