I just purchased a 4 wheel manure spreader that is supposed to be built by Oliver but the tag on the left front is missing.  How can I figure out if it is an Oliver and if so what model.  Also, both rear hubs are broken at the one-way ratchets.  Is this common?  Is there a recommended way to strengthen that area on the hub?   It came with good used hubs but I need to cut the old ones out and weld these in.