John I thought about doing this to the armature of a metal scout motor (2034-100.) These are cheap and I was willing to sacrifice one for scientific advancement. Couldn't figure out how to do it. If you succeed, please tag me and post pics!
As you said, swapping in a K&D no. 2 is an easy mod that turns the 700-series Hudsons into great runners on par with anything made up to the advent of electronic speed control.
