I don't think that anyone has addressed the fundamental issue for Beau:
Where are you going, what's your likely heat gain and how much heat and humidity are you trying to remove from the air?
In my opinion, 5,000 BTUs is nothing! We have two 16,000 BTU units (32,000 total) on our sailboat with no great big windows, covers over all the hatches, curtains on the ports
, an insulated deck
(balsa core) with a 3/4 inch air gap between the deck
... And it's adequate here in Mexico
. If we put up our Shade Tree awning, it's even better!
A number of folks around here have 5,000 BTU 12VDC systems. Nobody I've spoken to is happy with them. Too little capacity.
I think you need to investigate a larger system.... Or maybe a windscoop