Old Roy, I believe that the belt support brackets you need actually bolt
on the side of the tractor, under the belt cover. When you remove the belt cover, there should be two brackets, one short about 1-1/2", and one long one maybe 9".
If you go to partstree.com they have exploded assembly drawings you can look at. If you post a picture of the side of your tractor with cover removed, I may be able to tell better.