56 picup,
I think I can help you out, as a fellow Husker and 3 speed OD owner. They are great trannies and the stuff is available, even the relays if you want to go that far and spend the money. I am running the toggle switch method now and it's not that bad, but will update to the relays as the funds allow, they are both 75 bucks a shot. There is even a junk yard in Eagle, NE that should have your missing piece, if not I know another more reliable place that probably has a used one.

Willy 57
Working in CT, but will always is a Husker.