Greetings NDS and Diana!
The contact information for Helen Davis at Secretarial Services is as follows (quoted from the VAC web site):
Q: I need an owners and service manual for my Airstream. Where can I get one?
A: The first owners manuals were published in 1964. Prior to that, the owner received a brown envelope containing parts lists and other helpful information on the accessories in his trailer. The VAC has started making these available in the Members Archive section. A service manual with instructions for performing service operations did not exist until 1972.
You can get photocopies of owners manual (1964+) and service manuals (1972-1986) from:
Helen Davis Secretarial Services
PO Box 484 Sidney, OH 45365
Prices are about $33 and $70 respectively. After 1986 the Owners Manuals included available service information
RE: Locating Air Conditioner
The location for the air conditioner very well may not be one of the existing vent openings. With both my '64 Overlander and the '78 Argosy, the air conditioner was a "cut-in" operations at a point that was measured from the front-most roof "bow". In both cases, my dealer, Ace Fogdall RV, obtained the necessary measurements from Airstream - - in the '64 it was replacing an original Armstrong Bay Breeze and in the '78 Argosy it was an enitrely new installation.
While for many projects the '72 Service Manual would likely be applicable to your '70 model trailer - - I would hesitate to trust its measurements for air conditioner installation on an earlier trailer, but this information is readily available to Airstream dealers from Airstream - - and possibly to owners as well through customer support.
RE: '65 Owner's Manual
I have seen a few original '65 Owner's Manuals offered on E-Bay, and at least one or two offered at the Flea Market that is a part of the WBCCI International Rally. They typically sell for between $40 and $70 depending upon condition. The manuals from Secretarial Services will be photo copies, but the ones that I have seen are complete. Unless the '65 manual is significantly improved from the '64 it will be very generic as to systems operation - - it appears that the assumption was that the owner would use the individual manuals and brochures to learn about the installed options.
RE: Manual Availability via Net
I suspect that a big part of the reason that manuals were made avaialbe through Secretarial Services was to insure their continued availability, and to keep from overloading the office staff at corporate headquarters - - and I suspect that time/cost considerations are also a part of the reason that these documents aren't made available via the net - - the time committment can be considerable to scan and compile such a document into pdf format - - then the issue of drive space necessary to store these documents as well the bandwidth requirements (read cost) to offer such service to the public via a web site can also become an issue.
Good luck with your research!