Very nice work.
I have a few of the Bowser scale cars w/overhead operation at NYSME.(ModelEngineers.org) I have been looking at replaceing the worm and worm gear to slow the cars down. The stock worm and worm gear are a double cut. I beleive a ten to one reduction. By changing to a single cut worm and worm gear the reduction would be twenty to one, cutting speed in half.
Does anyone know a source for worm / worm gears. Inquired at NWSL last year, was neg. Had the worm but not the right diameter for the worm gear.