Nice looking build there, Karl. I'll agree with the others that the build, paint, and weathering are all well done, with three very minor exceptions.
First, the tailight and convoy light lenses need some paint. These can be easily rectified. Second, you should think about drilling out the empty pin holes on the ends of the spare track links (or add sections of rod to simulate that a pin is in place). The last item is not so easy. On the jack block, you have the grain of the wood going in the wrong direction. The steel bands are meant to strengthen the block to keep it from splitting when used on uneven ground. With the grain going with the bands, as you've depicted, there's nothing to keep it from doing just that.
Don't take offense at the "nit-picking". Just offering a couple obsevations.
