Casting number.

I found one on Ebay for sale listed as "Dual Pattern Mopar Bell Housing 2121863 Chrysler 1960s Dodge Slant 6 Plymouth".. it had a comment with it stating "170 225 Slant Six. Mopar (not sure what year) 61-62 possibly."

Hope this helps.

Thanks Dave, that was the bell housing I was looking at. I'm questioning the "Z" bar ball pivot on that one. I'm not sure that is same as what would be on a 65 A Body?