[goodyear1984]

all you need to do is get all of the r12 out and replace the fittings and recharge it with r134a.thats all my work has been doing for the last 12 years..when i took the test to be certified for a/c they say u have to remove the r12 and remove all the a/c parts to get all of the oil out and then re install every thing with different seals, but thats a bunch of crap.all i have done on every conversion is remove the r12 and put fittings on and refill..do that and get the r134a from a parts store and most of them come with dye in it so if u have a leak u can pin point where it is.