I guess there is a ray of hope in the otherwise wet, gloomy day. My wife was cleaning up and found a multi-legged crawling toy. I resisted my immediate urge to disassemble it since I thought my grandson might miss it. Well, I found a second one and that urge took over. The before and after is shown in the attached photo.
The great news is that this runs nice and slow and seems sturdy. However, it doesn't have the thick winding knob shown in most tutorials and there is another protrusion on the back side. I'll have to figure out how to deal with these issues. I searched for things that would fit over the thin winding knob and think a cap from a tire stem might work. It seems to fit and will give ample room to install a release pin. The question is whether it will slip under the pressure of a rubber band. As for the back side, I could cut it off but am afraid of damaging the inside mechanism either due to mechanical strain or heating. I'm sure these issues are easily solved...I just need to get to it!
Oh. yea, more good news. A small cable tie jams the gears and pulls out quite easily.