I have seen something similar on a '73 Westy.  These had the rear facing seat
fixed to the floor right behind the driver's seat (like a Wolfsburg Westy).
The a/c unit was under the seat.  This particular setup was factory installed
and actually the a/c had a compressor on the motor of the van and a condensor
under the van (pretty neat looking but probably a mess if you ran over a
branch or something).  The evaporator was under the seat and had a wacky
looking duct that actually came up between the seat backs of the front and
rear facing seat and then had two or three adjustable vents to distribute
cool air into the interior of the van (at head level).

I had never seen or heard of something like this before or since.  '73 was a
wacky year, what with a low-powered, expensive-to-fix engine installed, and
the old style pop-top roof with the hammock instead of the double bed.  These
aren't very desirable, but the A/C system was neat.
Also I don't see why you couldn't have placed a small 110v window unit under
the seat to get cold A/C while camping (plenty of room).  Just an idea.

Thanks,
Ken Wilford
http://www.vanagain.com
John 3:16
Phone: (856)-765-1583
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