Wtd: Slant 6 to A833 bellhousing (to go in a 1964 Dart wagon)

OK...more data

The date code on the transmission is 5192 - per the 10000 day calendar converter, that should be a build date of 10/15/1975 (converter here, if you haven't seen it: http://maxwedge.com/articles/10k.php )

So, that should mean it's an OD transmission, but...measuring the front input bearing retainer, it appears to be the 4.807" size, rather than the 5.125 (which I thought all the ODs used?)

Reading here - it appears that I'm looking for the later bell housing, but may need to have a ring machined to match the 4.807" to the 5.125" hole in the 1975-up bell housing:
http://www.slantsix.org/articles/4-speeds/ODA833fourspeed1.htm

(Rani, I think this indicates that there were A833's in 1964-1966 Slant 6s as well, and I've seen a few '64-'66 Darts and Valiants on ebay with Slant 6/4 speed, so I think that's a legit factory combo?)