I have not seen any comments about the need to add a spacer between the AeroWorks Edge mounts and the firewall. I plan to use an OS 91FX but in order to obtain the 5.61 inches between the spinner backplate and the firewall, I needed to add 3/16" plywood spacer. If not, there was not enough room to adequately drill the front motor mounting holes. Is everyone positioning the engine spinner plate this far out? I realize that this is moving the weight of the engine farther forward and everyone states that the airplane is nose heavy. Please advise.