Rich, there a lot of kits out there. They are all pretty much the same, two fittings, a can of oil and caps. Basically, you need to the flush threw the system, compressed air works, besure to drain as much old oil out of the system as possible, I always replace the dryer and the oriface tube, then add new oil and fittings. Vac the system down really good! I do it for atleast and hour to be sure to get all the air and whatever contaminates out. then charge it, don't go by the factory amount either, it takes about 10-30% less R-134 than R12. I did mine a 8 years ago, it worked great until I broke the line just before Sea Pirate last year, I still haven't fixed it, LOL!