lyle the gm is mk 10 pursang , but what u do is get some sheet metal (colour bond offcut from roof manuf. ) i used some stainless , cut it wider than the frame , make it in two pieces , the top with two tabs bent square down , the main part , goes down then follow the profile of the frame , then up , trim it to suit , it is easier to make a template from stiff card , stick it in the frame then scribe it to the outside of the frame where it seals up to the sidecovers , get the rubber from don , cut a hole in frount to suit bigger than the rubber , sica it in ,it is easy but have a play with some card , i,ve done two in my frontera,s