mine was like that too. i bought new channel from jim carter. there is enough in the coil to make all three pieces. make the vertical pieces first. it cuts easy with a pair of tin snips. use your old pieces as a template for the length and drill the holes. install both pieces then form the top piece to meet the veritcal pieces. be careful on the rear radius as to not to crimp the channel. you can fix it by flattening the sides with a needle nose. make it as tight fitting as you can. the forward the garnish is what holds the top piece in place. when reinstalling the window frame and its freshly painted you can put the rear piece in place and when you put the window in get it started in the channel and slowly lowering keeping tight up against the channel until the window is in. that keep you from scratching the forward part of the frame on the sheetmetal guides for the channel. then fish the forward section between the door and the window frame and put screw backin, bend the tabs back and reverse the operation of how you took it apart. when its done it looks like new and the window is tight and does not rattle.