Oh wow, small world.
Its strange, a lot of people haven't heard of the EPA friendly alternatives to R134a... I do some work of an importer and from experience, most imports with R12 systems are degassed prior to leaving japan, to avoid complications with the EPA when they land. Pretty much all the companies I've spoken to in melbourne absolutely insist on upgrading the system to R134a, which I reckon is rubbish. An alternative like the HyChill HR12 would be quite viable for owners of these types of cars.
But seeing as I have you guys to ask questions to, there's something that one of my mates commented on that might need clarification. When I told him it was a hydrocarbon based refrigerant he commented that "he wasn't gonna put natural gas into his aircon system in a skyline", especially since the aircon lines are so close to the turbo which can get very hot. What are the dangers of using HR12? I assume being a hydrocarbon it is flammable?
A list of recommended workshops would be ace, preferably those with experience with japanese cars and their AC systems. I'm not in any hurry, so take your time n enjoy the festive season. Cheers for the quick response too.