Gerry & Jae
I called the number Jae gave me, it was the Canadian Branch for Carrier. They were kind enough to give me the U.S. number which is (315) 432-6000 after talking to them, they directed me to the customer relations department which is (800) 227-7437. They had to look up the model and S/N in thier archives. Gerry, you were right, it was mfg in July 1973. I passed the information on to the buyer a few minutes ago, the seller wasnt being very forthright on the information he gave us on when this unit was replaced. Too bad the A/C mfg tags were badly weathered so that I couldnt read them. But I suspect they are old units as well, way past thier designed service life.
Again, thanks for the help.