The chassis under this
is 25mm overall, with a wb of 14mm.
Only 2 wheel drive, but pulls well with a bit of weight on it. The chassis used to be available separately iirc.
Just measured a Kato, it's 30mm across the outer edges of the flanges.
If at first you don't succeed, use a bigger hammer.
The only thing that keeps me sane, is the friendship I share with my collection of singing potatoes....
Never knowingly sensible!