I am willing to spend the time and a few bucks on getting a few of my Volvos comfortable for my my wife and daughters. I want to do this myself. All the systems have been discharged awhile and I now have the vacuum pump and guage set. I am confused (normal) and nervous (concerning a/c) about where the low side ports are on each and where to draw a vacuum from and where to charge the system. I have a '91 245 that I have to convert over from R-12 first and I am reading about that a bit. I have the kit and will have to replace o-rings, orifice (wherever THAT is) and the drier and replace the compressor oil. After that I am not sure where to draw the vacuum (at the compressor or at the drier) and where to charge the system with R-134 (at the compressor or at the drier)? On my '88 244 the system has already been converted by a previous owner and I know I will have to draw a vacuum, but where? Also, where do I charge it? At the pump or at the drier? I always thought that I should charge it at the port that is next to the line that comes into the compressor from the evaporator, which is the low side. Is that true and true of all models? It would be nice to have some graphics and step by step (dumbed down for stupids) instructions. A/C work is about the only truly intimidating work (besides tranny) I have left on these cars. Any help, directions, comfort, would be appreciated.