Reply to "AC R134 Conversion Mechanic Needed in Atlanta, GA"

If the system works now, it can be improved a bit by closing the isolation valves on your stone-age York compressor, then carefully unscrewing the smaller line connected to the brass evaporator valve under the passenger side dash. Inside the valve port is a tiny conical debris screen that is usually plugged solid with debris. No flow = no cooling. Soak the screen in carb cleaner or something to dissolve old rubber and carefully brush the rest off. Reassemble, reopen the compressor valves and with less than a can of freon to replace that lost, it should cool better.
Reworking any further will mean cleaning out the system, replacing the dryer, the evaporator valve with one specifically for r-134a, all the hoses for barrier-style o-ringed hoses, and the compressor with a Sankyo rotary. Sankyo sells an adapter bracket that bolts to the Pantera's York bracket, and the stock clutch wire plugs in with no alterations.