The good news is that Winnebago Industries is very good about posting information on their website. In fact they have a page where you can Download Winnebago Wiring Diagrams for free in PDF format. The bad news is that they only provide diagrams going back to the 1990 model year.
In your case your best bet is to call Winnebago at 800-537-1885 or by filling out an Information Request Form which is located HERE.
If Winnebago does not have the wiring diagram you need then I really do not know where else you would be able to get it.
Hope this helped.
Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.
Everything-About-RVing.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com.