Rudder Trim

[Capflyer]

My rudder needs a trim tab and not sure the best way to proceed. So far I have a foam wedge taped to the trailing edge which for the last 35+hrs has worked to keep the plane in perfect trim at all airspeeds but I really need to make something more permanent. My first thought is like I see on the spam cans which is just a strip of aluminum riveted to the trailing edge. It would be good to see some other ways as well. All responses and pictures will be graciously accepted. Thanks.