On a '90 740 Non-turbo wagon with AW 70/71 transmission, does anyone know how the reverse knob is held in position within the gearshift handle? I recently returned from overseas to find it sprung up from the handle. Nothing appears broken, nor can I find any broken plastic tabs in the gearshift handle well. Yet I can withdraw the knob and attached shaft from the shifter tube. The shaft has a groove near its transmission end which looks like it might hold a circlip or somesuch, While the knob sticks up some, it functions perfectly otherwise when moving the shifter. Thanks everybody.