Other people are posting information in this thread, VWG. Look carefully and you might find one with pages from a factory parts cattledog, explaining how and where this '66 with Slant-6/4-speed came to exist.
The A833 used behind 225 Slant-6s in Canadian-built '66s had the 3.09:1 first gear, too.
No, the next Slant-6 4-speed option (in the US and Canada) was the A833OD in the '75-'76 A-bodies. The F-bodies came after that.
