Hello there. I am buying a 1989 Range rover. the A/C currently is not working, not sure why, havnt checked it out thoroughly yet, but it needs to be switched over to R34a. the seller told me there is a shop that can do it for $300. I was wondering if anyone knows if this switch, as far as the parts that need to be replaced, is easy to do for the d it yourselfer, or if its something that should be left to the professional. I am by no means an expert mechanic but have done a lot of work on vehicles in the past, such as oil changes, changing water pumps, alternators, radiators, distributor caps, transmission swaps etc. Also, exactly what needs to be swapped out and what is the process for the conversion? I would appreciate any input.