I have been told this is a 1971 Chevy steering column by people with the next gen chevy trucks:

next gen steering column

It was in there when I bought it, so no idea how it was installed, but it is a straight, non tilt column with the automatic shift on it.

My transmission is a TH350 3 speed automatic.

Some of the vendors have the replacement shifter indicators available if you go to a 4 speed automatic such as a 700r4.

-Woog