How deep do you go?

[buckkoo]

Definitely keep the AC components. My 72 has a stock AC system with an upgraded Sanden compressor and chills the cab just fine down here in the heat and humidity of NC.

I would expect the efficiencies of the stock, Vintage and Classic air systems to be similar and would only consider aftermarket solutions for a non-AC vehicle.

As far as how involved a restoration, it depends on how much time, experience and $$$ you have to throw at the project. I would suggest a scope of work that you can complete in 3 years. (that way it will be ready in 4). Any longer and you'll be the guy on jack stands 10 years from now.