[Beelzeburb]

I believe that the rear a/c that ran the whole length was supplanted in '72 by the smaller rear unit. The period brochures tout "A two-unit air-conditioning system is new for '72." Looks like the front/rear setup w/ separate controls became available in the last year of production.

Be careful with the a/c unit as nearly 40 year old plastic gets a little fragile.