Nice work on the Vulcan trucks!  If they were available in S scale I would swap them out for the modified American Models trucks under the bashed Louis Marx bodies used to make the B&LE hoppers. These cars were 90 tons capacity as the new data by Ed Hawkins points out. The wheels used were 36" diameter. As I recall the decals were mainly CDS dry transfers with a borrowed insignia -- but that was a while ago in S and the alternative was hand lettering.
Chris Rooney