Hey All, I am working on getting my air conditioning to work again on my 1974 dodge van. Here are the basics of where I am in the process. I just installed a new compressor and clutch that is supposedly rebuilt to run r134. I added the required amount of the recommended oil (PAG-46) to the compressor through the oil plug on the side of the compressor. I will be replacing the receiver dryer, pressure switch, and the expansion valve. The hoses appear to be in good condition with no cracks or obvious damage. I tried finding new hoses with no luck, so hoping the original hoses will work for now along with all new o-rings and seals. The evaporator core looked to be in good condition when I had to remove it it to replace the heater core. The condenser core looks good for its age, but there is no obvious damage. My plan is to flush out the system and replacing all the seals and then evacuating the system to check for leaks. The main concern is what to charge it with. Should I go ahead and convert it to the r134? Should I use an alternative such as the hc-12a? or 12a? or ZeroR? Or just go old school farmer style and use propane? Now before you start with the negative comments, I have read about the dangers and concerns with using the various methods. Has anyone done this? What did you use? Did it work for you? Living in the southwest I would love to get the air conditioning working again. Thanks to anyone who can share some advice to help me get the cold air blowing again.