Okay, the good news,
it cools okay, no numbers yet, probably tomorrow.
Installed a low voltage cut for the ac unit so it wont pull my batteries dry
The bad news, apparently im only running on 3 batteries and i certainly have parasitic draw somewhere. So runtime on my bank of 3 (should be 4) was under 1.5 hrs before cutting power
Back to good news. Daytime, stopped for say loading/unloading, this will keep it cool enough that my ac wont have to fight everything the second i get back in the truck, and in tandem, less than 10 min to pull from 90 degrees down to 65.
I will absolutely look into getting better batteries and probably replacing all the alternator and battery lines.
At worst i can actually sleep in comfort while idling, at best it will help chill it far faster when i need it, and come nighttime ought to do much better.