Hey Glyn:
See you got down there in one piece (after all that).
You should check out RJs site for where folks installed AC units on trailers
like yours. There are pictures of '69 thru '71 Caravels (as I recall).
Units pictured were installed where the rear vent is located. A vent
location is typical for an installation point, although the vent itself must
be removed. In your case I believe that your vents are the rounded ones
like the ones on my '67. Hehr? If so, the rounded hole for the vent must
be cut out to a 14" square opening for installing the AC. I went the other
way and trashed the AC on my trailer and reinstalled an original vent.
Nasty job because the 14" square hole had to be restored to the rounded one
required by the vent (inside and out).
Re: the pan. You won't have one.
Re: the wiring. You will be lucky to have any. If you do, I suspect that
it will be in the ceiling adjacent to the rear vent opening.
RJs picture collection can be found at:
http://www.vintageairstream.com/archives/index.html
Good luck,
GQ '67 Safari
4082 in CA