Light Switch Rotary Plates: 1928, 29-31, and a Mystery Plate:

[WerbyFord]

I’ve been troubleshooting multiple issues with lights & horn on my December 1928 Model A.
Traced them all back to the Rotary Plate on the steering column. Original Rotary, new wires soldered to it 50-60 years ago (we got the car when I was a kid!).

Here are a couple helpful threads I came across:


From 2013:
fordbarn.com/forum/showthread.php?t=122368

From 2016:
fordbarn.com/forum/showthread.php?t=196142


Along the way I scrounged my dad’s old parts bin from the 1970s and found a Mystery Rotary Plate.
I’m wondering if anybody here has ever seen this.

As you may know there’s 2 basic Rotary Plates for the Model A as shown in all the Books:
1. Thru Feb 1929: Rotary Plate has 4 contacts (plus horn in center). Brass Ring that rotates from the steering wheel switch has 4 contacts that connect them. 2 Lighting Positions: Goes left for brights, right for dims.
2. Two variants: Both have 3 Lighting Positions, all same direction on the switch.
a. 2a: Feb 1929 on: Rotary Plate has 9 contacts (plus horn in center). Brass Ring has 3 contacts to connect them. 3 Lighting Positions: Parking, Bright, Dim.
b. 2b: Feb 1929 on: Rotary Plate has 9 contacts (plus horn in center). Brass Ring has 3 contacts to connect them. 3 Lighting Positions: Cowl, Bright, Dim.

Naturally there were no 1928 Rotary Plates in the 60 year old parts bin, they were all 1929-1931 style with one exception.
3. Unknown Years: Rotary Plate has 6 contacts (plus horn in center). Brass Ring has 3 contacts, 1929-31 style. 2 Lighting positions, Goes left and also right, 1928 style.
Anybody ever see a switch like this?

I’ll try to include pictures of the Rotary. The “clock” I’m using is viewed from the drivers seat.
Wires are too old and dirty/faded to read colors. If I really use my imagination I can see a Yellow+Black tracer wire at Noon, seems thicker than the others (hot from generator?), cant read any other colors.

Pictures from the back (wiring side)
Noon-3oclock
3-6oclock
6-9oclock
9-12oclock
And a picture showing the Rotary, 6 contacts and 3 “off” contact dents, and the Brass Ring with 3 contacts.
(Edit ok I added the pictures)

Any ideas on what car this Mystery Rotary Plate is from?