For whatever strange reason, I opened GIMP and actually worked on this project today.
I felt the upper portion of the bike was too large vertically, so I made a selection and scaled it down a bit. Also, the body work around the seat was too steeply angled, so I rotated that area, and re-drew the lower corner back there as well. I like the result. I had the drawing of the driver cut out and scanned a long while ago, he is now dropped into position in the layered file.
Also I did some work on the front tire and wheel.