At some point a PO swapped out the rear on my 54. Looks like they also modified the mounts. The rear looks much like the one on my 55.1. I put some pics online (link below) and was wondering if anyone can help ID it. There is a small tag screwed in on the drivers side and look like it has 139 stamped on it. Thanks as always.

http://s1162.beta.photobucket.com/user/miami54hydramatic/library/rear%20end%20on%20the%2054