Welcome to you and your C-20. Someone will surely chime in with answer to your tire/rim question. I do not know the answer to that. As far as your picture question, Provide a link to a photobucket (or other photohosting) site. We will be able to look at pictures that way.
HB


~ HB
1966 Chevrolet K-10 | Ghost: formerly Flappy Fenders | In the Stovebolt Gallery
1962 Chevrolet C10
1962 Suburban