Update. Running it now mid day sitting in a parking lot in the sun on a partly cloudy day. Van interior was 31% humidity and 91 degrees, ambient temp outdoors is 86. Ran it on high for about 10 min and got down to 80, switched it over to low and after about 30 min of running total, currently at 60% humidity and 77 degrees.
I'm impressed. Doesn't seem to be using too much electricity either, and I think my system can sustain it