I forgot to mention you can use parts from a regular Singer 15 to do this also.
The machine I used in the pics above was a total mess. Rusted, coated with a black carbonized gunk that took denatured alcohol to get off ( hard on decals ), the wiring was a dangerous mess with petrified and gooey insulation on it.
I paid a whole $10.00 for it for the express purpose of learning how to rewire a potted motor. I did it, I got it all cleaned up, rewired and it sews just great. But it's still too ugly, and I've got too much time and effort in it to sell it, so it is one of our user machines.
It would have been far easier to convert it to a regular motor machine like my experiment, or to a hand crank or treadle machine with parts from another derelict machine.
Joe