Hi Rob,
There is actually black under the desert sand paint. I tried to sand it a bit to show, but not too much. Looking on reference pictures they just sprayed over everything, tracks, road wheels, antenna, etc. I have a picture that looks just like that road wheel.
Yes I agree with you about the mount. I was going to do something, but forgot about it as I have dragged this build out. Now that I was reminded I will probably do something about it.
I also realized later the ammo crate that is mounted on some 90 deg brackets is not attached in a realistic manner. Not sure I really care at this point as I am ready to move on.