Currently it is a square back, 110amp, it just isn't cutting it. I can't run the car for extended periods without discharging the batteries, driving it at night it completely out of the question too.
It's VERY possible that it's "not just the alternator." If I were you I'd do a load total. Take EVERYTHING that runs on such a cruise, and obtain current readings. Some you can look up, like the model of your fuel pumps, etc. Some you will have to measure. There exists large current shunts so you can read large value loads. You have have something wrong that is preventing the 110a from fully performing.
Even the "lowly" 110A unit is a LOT of amperage
Also check the battery and system running voltage. "One wire" setups are particularly fussy because the sensing is on the "wrong end" IE at the alternator output, and it simply goes downhill from there.
