The dual electric fans + AC are a "game changer". You need an alternator that has very good idle output (~80 amps) and can handle high load factors. None of the stock looking squareback derivatives even those rated 100 amps can do it. Max idle output on those is 50'ish amps.

Alternators I know of that can are the 140 and 200 amp Powermaster Delco based units, The 120 amp Denso and the big 100 amp Chrysler unit mentioned above.

"With AC" has different alternator brackets that make it harder to fit a non standard alternator. The Powermaster Chrysler adapted Delco's will mount in OE brackets but are a tight fit at the back vs the head. I tried one with Ed heads and no go. Maybe it would work with OE heads.

The Denso would take some degree of bracket modification.

For all of the above reasons, I went with the big heavy 100 amp Chrysler unit with brackets from my core '78 Cordoba engine (70E BB).


Good luck!