I recently had the a/c serviced on my 1983 300d and the mechanic also injected dye to see where the leak might be. One month later, it failed again and on inspection, the dye was showing up on the compressor itself. The shop says a new compressor, receiver/dryer and other associated parts to the tune of about $700 and together with labor the total bill is about $1300. My question is this: Since there is nothing wrong with the compressor except that it is leaking refrigerant, is it possible just to remove the compressor, install new O-rings and then reinstall and recharge the system?