Early Abody 4 Speeds!!

Jim Lusk said
'66 A-body had the slip yoke and 3.09 first. 3.09 first also had 904 sized output shaft.

Is 66 the only year with the 904 sized output shaft? Later ones had the 727 sized shaft?

Also, was 66 the last year of the 3.09 low gear until it reappeared in the seventies in some E body trannies, and of course the O/D 4-speeds?

I've always liked the 3.09 low gear with 3.23 gears. Overall low gear ratio with that setup is 9.98. Quick off the line, but with those 3.23 gears could cruise at interstate speeds. When I ruined the mainshaft of my original trans, I put a 69 trans in it which had a 2.66 low gear. All of a sudden, my 340 was a dog off the line. Just amazing that it made that much difference. After a couple years of that, I found out my original 3.09 gearset, which I luckily had saved, would fit in my 69 trans, so in they went.

Edit: A 3.09 low gear with 3.23 rear gears give you almost exactly the same overall low gear ratio as a 2.66 low gear and 3.73 rear gears.