My first go at making a repair panel for the sill...I'd like to replicate this line, tried hammering a small sharp pinch at it but not doing it....any ideas please
take a block of hard wood / alloy / plastic , cut a step into it then put it behind where you started , use a couple of vise grips to hold it in place , then use a long bit of flat to knock the rest of your repair patch over the lip and it will form no bother .
practice on a bit of scrap first.