With the skills you have, why not get a 1:35 scale model of the truck you want to build, and then just buy the 3D printed wheels for it from shapeways. There is a guy that has really nice rims and tires for all the popular US trucks from WWII.
I want a CCKW and have been thinking about doing this. Firing up my casting bench has also crossed my mind too but I really don't have time to do that much these days.