Thank everyone that has sent me tags and threads on this subject. My approach is to pull a vacuum n the evaporator tubes sticking thru the firewall - pending I get adapter fittings. If this holds I will then proceed. My plan is to use original R12 refrigerant and a new original OEM filter drier. Use the original condenser (initially) Per all the feedback it looks like a Sanden SD-510HD compressor New - unless there is another better choice?? The only unknown is the compressor mounting bracket - I see an M5 is recommended I don't know the PN - unless there is another better choice? New hoses with fittings that fit the system. I will use the original fan. I can upgrade the condenser to parallel flow with a new fan later if required. R134 and R12 are similar in pressure points however have different boiling points. R134 actually extracts more heat per pound but to achieve this a larger condenser coil with more air flow is required. The TXV probably needs to be revised for 134 to achieve balance. So all in all I'll stick with R12 if possible save a few$$ and see what performance is achieved. Any advice on the mounting bracket PN and or compressor is much appreciated.