I want to put in the Variable Orifice Valve on my car to help improve the cooling, is it a good idea to change out the Receiver-Drier when I open up the system. My car is a 1994 940 factory 134 car, where exactly is expansion valve located, and is this something I could do myself?? Opening up the system seems easy enough, it's just on charging it back up seems a little confusing. Draining the compressor oil and adding new oil, vacuuming the system and then adding freon, is this the order it goes?? Also there is only one high/low (not to sure which) side port on my car? I've seen a lot of posts for the conversion from 12 to 134 and just want to clarify if it is different for a 134 car. Also can a person clean or see if the cooling coil is dirty and needs cleaning??

I also have the air going down to the floor under acceleration on my car, but that's a whole nother animal, I looked on the board and I think that it may be the vacuum servo motor.