Volkswagen: Air Conditioning Conversion, jetta 1, service ports

Question
John, I am preparing to convert my R12 Air Conditioning system to r134a.  I am going to replace my receiver/drier and expansion valve, but what about the compressor?  Are there any tests I can do in order to see if it is working?  Also, my car was made in Germany, so it has two smaller service ports that are the same size(low and high), not the standard r12 set of ports.  Are there any conversion kits available for that setup or do I need to find a USA made model's hoses(and service ports)?

Thanks,

Matt

1988 VW Jetta 1.8L SOHC (RV engine)
VIN: WVWEA0168JW280335

Answer
basically all you can do to test it is to make sure the main shaft turns without too much strain. as for the pipe work, r134a requires a vacuum to be created in the system on both sides to draw in the gas. i do not know if the is any way to convert it from r12 ports to r134a ports. if possible the easiest way to ensure compatability is to replace the pipe ( as r134a is carsonagenic and the oil is cancerous so leaks are dangerous )