Since you already have the 5000 BTU window shaker and you have a 6 foot wide CT like mine, what about simplifying things and just solid mount your shaker? You already don't mind making the hole in the side of your cargo anyway so what the heck! You can save all the work of making that sliding mechanism and have a stronger mount to boot. If you had an 8 or 8.5 foot wide CT or even maybe a 7 I can see it being a bit risky having an A/C box projecting further out to the side than anything else, but for a 6 footer, why not? I figured that my wheels stick out to the sides 11.5 inches already and the shaker projects out just 7 inches, so it's inboard of the furthest part projecting out to the side already. It uses just 3.5 inches to the inside too, making it pretty unobtrusive.


I think a side mount for a wall A/C make more sense. Bugs don't get mashed into the condenser nor rain pelt through when you drive.

(I have a ramp door for my ATV, so a rear mount A/C in a false wall was not an option)
b.bodemer's slider is nice, very well done, but you need something like a cabinet on the inside immediately below the A/C's access door so that it can bear the weight of the A/C when it is retracted. You could build some bracing inside to hold the retracted A/C up but then that bracing would be intruding into the interior space all the time. A cabinet like b.bodemers would be the answer. Two birds and all that.
ps. Since this photo I found that a pet flea comb makes a perfect A/C condenser fin straightner.
Whoops, I just saw your other A/C thread where I already uploaded pics.