Thank you every one for your opinions. I will go with after market A/C. I don't remember how good or bad the chrysler systems were in the late 60's. Lived in PA and did not need A/C very often.
Were it me, I would go with a hybrid. --- Use the factory A/C dash frame, Heat-A/C box, and stock ducting from the Charger, and go modern under the hood.
The stock evaporator is far more efficient than any of the aftermarket offerings, and a new rotary type compressor and parallel flow condenser, is equally far more efficient than any of the old stuff.
Stock A/C venting is better than the aftermarket versions, so for a true improvement, the hybrid is the best way to go.
Converting a non-A/C firewall to an A/C version is fairly easy.
I do lots of A/C work on old muscle cars for other desert dwellers and the hybrid is better than either stock, or aftermarket, everytime.
As a side note, are you going to part out the rest of the Charger? If so, I need the passenger side "chunk" (the 1/2 pillar that holds the door latch, and the rear quarter mounts to). If you have it, please let me know.