Window air conditioner with a twist

It would work but you'll need to seperate two air channels. One for the intake on the side and another for the exhaust out the back. You dont want them mixing but if you can do it, I think it would work.
Please update us if you go forward with the plan!

my only thoughts involve front air pressure while driving
you don't want it to turn into a 'ram air'
too much hot outside air being forced in, that the A/C can't cool it
and cold ram air in the winter, even with the unit turned off
you need a way to close it off in winter
and restrict it in the summer

if the air flow is up from underneath, should greatly lessen the ram effect, but that will be really hot air from the road surface

I did consider the "Ram" effect.....I'm thinking it would require some type of damper....as I figured, lots of tinkering. I guess I'll mess with it after taking care of the many other projects I'm always working on or changing. LoL

What about one of the "portable" units?

I've tried a couple different portable units and while it offers some relief, the bulky 6" hose(vent) and the size(even on the compact ones) makes it a bit tough to travel with. I told my brother on my last trip I was going to take out the front passenger seat and place a larger portable air in it's place. It was a thought but not to feasible.

Many years ago Professor95 did a mod where he took a 5000 btu window ac unit and put it in a dometic base and plastic shell. I'm sure Mr. Wizard or 2oldman can find the post from way back in the day.

It worked well from what I remember - it might be worth looking at what he did in order to give you ideas on what's possible for your situation.

Well.. Back in my Trailer days, both the PUP and the 13' Scamnp. I more or less did just that (had a window A/C in the PUP it was under the front bunk into the main center area and in the Scamp over the top (Storage only) bunk in the front window) Worked fairly well. Sounds like a plan

#2 You can likely get A/C fixed for around 1,000 or less.. YOu likely wont' have to replace EVERYTHING.. (That was the cost of a new compressor on my Gasser. might actually be cheaper on a big D due to access making the labor less but frankly.. that's a small portion of the bill).

I have (3) 5,000 BTU units aboard Quicksilver but none are for use in motion. Getting rid of condensed water should be planned for. In an uninsulated area with lots of glass, a 7-8,000 BTU unit would not be excessive IMHO. A simple 4" duct hose connected to the condenser inlet can be "rammed" with no ill-effect. Condenser outlet needs to be configured to "educt" which may need a sheet metal shop (HVAC) created duct to go forward, then down, and exit to the rear. From screwing around with my three Gold Stars I will assume your dash unit will not do so good at low vehicle speeds but work fine above say 20 mph. The evaporator water was my biggest challenge. I used an HVAC galvanized tray, sprayed undercoating on it, and used a 1/2" hose. My unit's trays have a 15 degree tilt toward the condenser, and are boxed in. I fitted scrubber pad gross air filters to condenser inlet ports to act as a rough air filter. In your case would imagine, planning a serviceable way to clean condenser fins would be important.

Shove the unit forward against a foam seal then use a condenser inlet duct with magnets attached to clamp to the side of the AC unit? For a removable side duct N52 grade neodymium magnets would hold tight.

I'm sure the HVAC sheet metal shop would have plenty of ideas for ducting. Some of these guys are wizards. "Lisle" the guy who did Quicksilver was a wizard not only with sheet metal fabrication but also with ducting ideas.

When I was younger I loved projects like yours. The best of fortune to you, and please report back.

With Quicksilver I can plug into a Mexico RV park grade 15-amp receptacle, close off the bedroom and while neighbors may curse not being able to use their roof unit my Gold Star unit keeps the bedroom cooler than a single all-RV roof air unit ever did.

Thank you Mr. Wanderer.....I kinda figured some sheet metal work would be in order to get the exhaust/intake somewhat correct. I have a small unopened 5000 BTU unit laying around that I got years ago for a song and a dance, I may just use that one as a sounding board to do a bit of trial and error. :-) LoL

Read specs carefully before ordering. Many of the "larger" window shakers run on 220 VAC. Unless of course your generator can supply that...