Hello, my name is John Kooijman from The Netherlands, Europe. I have a 67 Riviera and need some info. It's about the cases for a Positraction for the rear end of this Riviera. On the case there is a 3-digit casting number (on the case itself). Can someone please let me know what these numbers are for the different cases (for the different ratio's of ring and pinion that fit in it) Hope this is clear enough. Thanks.
