I have a 1956 Ferguson F-40. I'm needing to replace the rear wheels. The current wheels are 4 rail adjustable rims. My question is can I replace the rim with a 6 loop rim. The rim size is 11x28. If no one knows. Could you please point me in the right direction.The 4 wheel drive MH was not a real success. They were obviously heavy on the front end. Though definitely ahead of their time were cumbersome and did not sell well. I would love to find one in the back of a barn though.... About the Fergie on top, there is always a cloud floating over the MH and Ferguson merger, I can't really keep it straight Mike, but as a result there are a few unique models produced during that time that have become very much sought after.