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. 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
(937)492-8885
Prices are about $33 and $70 respectively. After 1986 the Owners Manuals included available service information.
GStephens