I fell asleep thinking about roof top a/c units, cold air returns and HVAC design.
Photo from Reiner Group,Inc.
I thought would be easy enough to build something like this? I could even hide the batteries for the lighting inside? This is one I made this morning. It looks too large, but it's a start.
I found another website with more mechanical information that I will ever need!
I have to go to work now. Hopefully, I can get my mind on my work and off building air conditioners!