When I bought my '76 the original top had a glass sunroof in it (!), but the seller had another top laying around and I took that instead. It didn't have the liner installed, but it seems I'm also missing a piece across the front, there's four unused screw holes across and the parts book says a piece of padding should be attached. Looks more like a metal rail across in the parts book picture.
Would anyone have some good pictures from a late model (preferably '76 or '75) targa top's insides with everything on it?