I've just finished restoring a Dr. Dude and ran into a small issue. I replaced the slingshot switches on each one with new ones, and wired them exactly as they were before. I double checked and no wires are inadvertently touching anything they are not supposed to.
Yet when I hit the left slingshot, the left flasher (Magnetic Personality) fires, and when I hit the right slingshot, the Drop Target flasher on the right fires. This occurs whether they are LED flashers or incandescent. Of note, the flashers fire regardless of whether the coil fires when the slings are triggered so I don't believe it to be coil related.
I've attached pics of the switch wiring. There was already a diode on one of the two sling switches (the one with 3 lugs) for each slingshot and I carried these over from the old ones. I'd be surprised if both went bad and that's the cause. I think these are 1N4001 diodes which I have on hand but not sure if new ones would fix the issue.