It's a very similar shape to the original just extened out the sides to fit the Wheels and added an “Axel” to hold the 2 wheel rods and wheels. Assemblies very easily, just need a small amount of glue to piece it all together. Glue the wheels to the rods, the rod spin freely in the lops on the end of each axel.
I printed these at .05 and they came out great with only minor cleaning required.
The author remixed this model.
Added wheels, an axel and extended out the sides to compensate for wheel arches.