I'm just using folded paper, I use the folded paper as a frame stencil for the cage and lots of eyeball work with reference photos, what I've done is measured the inside of the cab side to side and then front to back once that's done I use styrene tubing and brass rods inside the tubing for support every piece should be bent into place so that it fits if things are squeezed into place it warps the whole thing for the frame I cut styrene sheets and glued them together to make square tubing and put filed copper rods inside the frame for rigidity in the photos you can see I had to cut the front end and lengthen it I'm going to be working on the truck some more in the next little while, until next time happy building
Timothy Auger
