I don't know if you read the whole thing...

But, Lazer Works has the Midwest Das Little Stick short kit as well. Apparently, they also have a source for the plans.

Midwest turned them over to AMA, so they're probably essentially public domain now anyway.

The DLS is a 46" span, so it might be the ideal size you're looking for.

I'm not making any recommendations on size versus engine. I'd guess it'd work either way. Depends on what you are looking for.