UncleRod,
I have enclosed a schematic of a '57 directional unit. It isn't the greatest but it might let you see what's inside before you tear into it.
If it's a broken component that caused the original to be abandoned, I'll bet it would be easy to diagnose and repair. The hardest part might be getting the steering wheel off.
Before you ripped it apart, it might be interesting to see how many repair parts are actually available for the switch. Good luck.
Stuart
