Right off the bat you have a problem. Units as old as your used R-12 which you no longer can get. So if the system is opened for any reason you will have to refit to R134a which is going to cost you, and I've heard the kits don't work very well due to the smaller condensor used for R12. Unless your turning the compressor there is no way to check the operation of the system I know of. Check your heater hoses to make sure your water cutoff to the heater is on the 'feed' hose to your heater. if it isn't the you will get hot air from the heater.
