folks heres a cheap and EASY idea i came up with..   get one of those cheap
small window a/c  units and build a 2x4 cradle for it to sit in up in the
poptop luggage rack and strap it in there.  then make a  snap on canvas or vinyl
boot to attatch it to the poptop canvas front window.. boom..there ya go.. blows
cold air right thru the front window screen into the poptop.. condensation
water drains right thru the poptop luggage rack holes and down the raingutter as
it normally would during a rain.   it stays up there all the time during
camping months and no messing with a window contraption to hang it from your front
pass door and having to lift the heavy unit up and down off the door
everytime you want to drive as some have done...  you just unplug it and drive away -
it stays in your poptop luggage rack.   cheap and easy and practical.
worried about aerodynamics?  drive a porsche..

chris