I don't think its a Caddy either. Nudie favored 64 Pontiacs (did only one Caddy, I think), and I am pretty sure this is one of the Pontiacs, just not a Bonny. Anyway, its not the car, but the location and what goes on there, that is the obscura here.
not a Pontiac to my eye looks like a de Ville to me - see those huge front side lights? year looks more like maybe 1970