$40 for a can of Freon? I think /not/.

You'll need the adapters that screw on the ports as the r12. are different in size than r134 . Converted my dads 67 coronet. Evacuated it and serviced with r134. Maybe got lucky but that was two years ago and the vent temp is still about 40 degrees below condenser air temp. Has about 10000 miles since done. As a side note that system was an ad on from Sears and roebuck. and not factory installed.