I have the opposite opinion of most posters. I had a 1959 with the side mounted spare as my only 4 wheel vehicle for several years (long ago). I never got a flat with it and the spare was always in the way when loading or unloading from that side of the truck. I finally got a smooth fender and mounted the spare under the truck. I was sorry I hadn't done it years earlier. If you don't carry much in the bed, especially up front it probably is not an issue.
Chuck