If you cant get pics, take some measurements on each side. Measure from the frame to the edge of the disk brake with the truck on level ground. Then jack up the truck and (support it somewhere besides the arms) then take some measurements. I think after you do this you will figure it out.
I had a '75 camaro once that had the same problem, turned out to be the prev owner put a fender on the drivers side from a later model car that was flared out bigger
