This is a very pertinent topic for those of us in California who own cars with the Freon Air conditioner.
I own a 1987 Volvo 740 Turbo Wagon (and 96 Volvo 960).
Any ideas and recommendations as how to convert my existing Freon (R12) based A/C to the new R134a without much expense.
I bought a kit from this company which claims to do just that w/o having to mortgage the farm.
http://www.id-usa.com/retrofit.htm