[waytogo]

Try using a drill angle guide to get the proper angle cut.Do it first on some scrap wood .After u have got the correct angle get 1/4 in aluminum stock for the backing plate.The ho e u have cut should be longer than wider,drill and tap the plate for the proper size macine thread.dry fit the plate on the wood first.You have to make sure that the wood is the same width as the gunnel so eveything will line up
hope this helps
Dave