I really liked both designs I remixed from, but I saw a bit of an idea to try. These WPL and JJRC trucks are pretty darn light weight. Which, in theory, could be bad for traction. And in some models they're a bit top heavy and can easily tip over. So in order to combat both problems with a cheap solution, I decided to add weight in the form of copper BBs or lead shot to empty areas anywhere I could find them in the chassis beams and bumper area. As they were, it was not nearly enough to add significant weight. So I remixed and rebuilt to increase empty volume for adding BBs, lead shot, etc and gluing in place with hot glue or epoxy or whatever you like.
I also saw the thin walls for the screws as a weak point so I increased the amount of plastic available for screws to bit into.
It should work with any of the similar 1/16 scale metal C channel chassis trucks I think.
6/10/19: Added V2, I just discovered that some models of truck bed have a protruding tab that needed space to insert. So the choice is to either clip the tabs off the truck bed or create slots for them, so I created slots. Hopefully nobody ran into that problem before I noticed it.
6/16/19: Apparently some beds didn't work with the previous v2 so here's v2.1.