Thank you for all the suggestions. Are you sure that expansion valves for R134a had a different size orifice? The description of expansion valves state compatible with R12 and R134a therefore now I am a bit confused. I was planning to replace the expansion valve anyway.
The IPSCO idler pulley looks like the way to go.
I can make the new hoses to have flared ends for the condenser and evaporator, or I can have them made with the newer O ring type fittings and then use adapters. The adapter adds another place for a possible leak but if I ever wanted to upgrade the evaporator or condenser there would not be a need to replace the hoses, just eliminate the adapter. Any opinions on which way to go?
I am still debating what to do about the compressor. The Sanden 508-type compressor offered by Summit is made by Vintage Air, are these made in the USA or China?
Compressors seem to come with PAG oil. If I am replacing all the hoses and flushing the condenser and evaporator should I still dump the PAG and go with Ester oil instead? Seems to me that I should be able to use PAG as there should be very little to no residual oil.