The unit who's link is in Post #5 is rated at 550 watts. That equates to 46 amps at 12 volts. I am not sure if my alternator can handle that. Plus, the startup current is 75 amps, which my battery could probably handle.
Some extra room is needed for the electric compressor. I don't have that room in my car. It probably means that you need a coupe or roadster with a trunk.
AC experts say that the cold air must be directed towards the passengers or it is not effective. I am not sure if that is the case with the electric unit. Plus, it would depend on how well the car is insulated.
My thoughts were to gut the tank and install the AC evaporator there. I am not sure if I want to do that because the cowl tank is such an integral part of the Model A experience.