Well seeing as I have already done a 25pdr gun, and have an HL truck on the way I thought I would start on a Morris Quad. I figured that if I do a 1/16 shell and its not the right size for the axle width on the truck, I can just scale the whole shell up or down in Cura or Openscad and everything will stay in proportion.
The main shell is done, now need to start on the detail, and yes it was a complete pain to do!
If all else fails I can just do the whole thing as a static model for a diorama.