That is the nicest C50 I've seen. Here's a picture of the trucks I drove when I was in high school helping with wheat harvest - they have removeable sides so when the grain was harvested the sides came off and it hauled straw. One of them had a 350, but the other had the straight 6 (not sure on CI). No radios. It was a slow trip fully loaded with grain no matter which truck you ended up with. These trucks don't do much work anymore, but the owner will keep them forever.
We have to see more pictures of the interior, engine bay, etc.