There are 3 versions of the 3 rib.
First is the acorn nut version early '68.
Next is a 3 rib that came in late '68 to '71 buses.
If it hadn't been molested, it usually had the smooth bell housing and was used with a Beetle style engine.
Last version was the one Odyknuck described.
Had the mounting bosses on the bell housing to support the pancake style T-2/T-4 engine.
Long spline, stronger 1/2 gear set. Best of the 3 rib bunch.
This is a good thread from TOS to differentiate most VW transmissions.
http://www.thesamba.com/vw/forum/viewtopic.php?t=143138
_________________
Gary
Turbo VW Sand Racer
Polaris Ranger
"If you don't run into the Devil every once in awhile, you must be going in the same direction!"
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