Regardless of what you do inside the car I would advise swapping to a modern compressor.  The original compressors are heavy, use like 20HP to run, and don't run as well on R134a.  A Sanden compressor uses like 3HP to run and is much lighter.  The OEM Fox compressor is also a good choice, especially if you are going to run Fox front dress. 

TKOPerformance wrote:

Regardless of what you do inside the car I would advise swapping to a modern compressor.  The original compressors are heavy, use like 20HP to run, and don't run as well on R134a.  A Sanden compressor uses like 3HP to run and is much lighter.  The OEM Fox compressor is also a good choice, especially if you are going to run Fox front dress. 

I agree w/TKO, I'd go with the new A/C systems they are much better than the opriginal.
 

I went with a Classic Auto Air daily driver.
It was new/used…partially mocked up for some kind of custom build.

One of things I like about their setup is that it doesn’t look like an after thought when mounting the condenser which is visible in the grille.

I ordered the necessary parts (serpentine compressor and brackets) to install with a Foxbody accessory drive.

I like RV6’s heater replacement for interior.
He has dehumidified defroster too.

I have to run a/c and heater at same time to get same result.  I have under dash assembly in my interior.

For a driver, I’m really satisfied with it.

I had factory AC in my 66.  While it cooled great, the defroster just did not work well in the summer. Seems like it rains on every bash trip and it was not good.
I converted to Vintage Air in-dash system. While it does not cool as well, the defrost function makes up for it when needed. And infinitely variable fan speeds and mixing doors are real nice.

I went with the Vintage Air "Stage IV" system and and happy with it.