I have been told that they really don't have to change out all of that to use R134 on the auto air conditioning. They can use it without changing everything, just empty the freon and retrofit it and then put in the R134. Hey, if it doesn't work you can always change out the compressor /exchanger and dryer. You don't have the corosion out there I don't think so it may not need all of that. They may be seeing you coming on that one, Kiddo. Ask some of your mechanic friends who have converted their old vehicles if you can do it. A buddy of mine did and it worked fine. He did the same thing with a window AC unit, a big one, and it is putting out colder than ever and not freezing up. Just a thought to save you some bucks.