Update: In cleaning it up I can barely read 'OLIVER' on the left front of the wooden box and 'SUPERIOR' on the right front of the wooden box.  I found a picture of a 75 (click on the following link to see the 75 <!-- m --><a class="postlink" href="http://www.tractorshed.com/gallery/iphotos/i402.jpg">http://www.tractorshed.com/gallery/iphotos/i402.jpg</a><!-- m -->  ) mine looks like this one except mine has rubber tires.  Was it converted to rubber or is there another model that came with rubber?