I'm thinking this is one which will require going direct to Winnebago for info/ drawings as they only post online back to 1990,leaving us cold for info.
There is a small help which I do not know if it applies to the older RV or not?
At some point Winnebago started labeling the small wires.
You may/may not find these on your wiring??
But IF you do there is a list to "decode" where the wire comes from and goes to.
Reports say folks get good response when calling Winnebago direct?
Their home page for info?
Good luck on the chase but it may be a trek!