I think I’ve done my research and am not asking a question that’s been answered over and over - but if I missed something I apologize. Dealing with the age-old RH-5 question on my 1950 6400. Backs are widow makers fronts are not. Has anyone found a useable adaptor to take 4.75 x7.25 pattern out to 10.25? My son is a CNC machinist and we’re preparing to make our own - but I’m wondering if anyone has come across an off the shelf option.