I have a '64 Wildcat convertible with a sagging main top frame rail that prevents raising the driver door window completely. The sag is at the first hinge, near the rear of the driver window. There is a square-head bolt at that hinge, accessible when the top is half raised, that allows adjusting the rail/hinge downward (wrong direction for this problem), and it has already been backed off to assure that it is not the cause of the problem. Does anyone have any experience or suggestion that might help me to correct this?