I spent the better part of a day replacing the compressor and the rec. dryer. I had a mechanic convert the system over to the R-134a. It worked great! I never had the R-12 in this car, so I can't compare the two. The next morning I got in and turned on the air, and there was none. I took it back down to have it tested for leaks. It was leaking right at the mainfold. The compressor I bought had the wrong instrutions it it. It didn't show how to install the o-rings for a stepped port compressor. I called the guy I bought it from for some guidance. He told me to use the yellow along withh the green o-rings. What he failed to tell me was what to do with the short sleeve that came in the retrofit kit. Has anyone done this before? If so can you tell me how you used this kit, since there are no instuctions. Any help would be greatly appreciated. Thanks.