I was thinking that with the pushbutton shift and all, it should be a 727. Also thinking that the 904s didn't happen until the LA motors happened? Which would mean that 727s were behind Slant 6 and A-motors, too. Especially for fleet use, but if that's the only automatic you have at the time, different versions of it for the different engine families.
An interesting wagon survivor. Especially a 9-passenger version.
CBODY67