Nice job. Been doing that myself, the last couple of snowy days. Been making some other stuff also such as Casey the hound, that converts to Casey the combine. It is a kids pull toy, complete with a cog in his belly that makes a sort of barking sound.
If I can get the build time down with these proto types, I may accompany the wiffey to some craft shows next spring. I have a genaric tractor also that I can paint any color