I have a 1979 300SD, and i took off the panel with all of the climate control buttons on it to try and take out the tape player. in doing so, the piece that regulates the buttons for heat and defrost broke open and 4 wooden pieces fell out, the looked like long jigsaw pieces. i don't know what configuration to put them back in, so now my defrost is stuck on and the other buttons won't work. does anyone know how those pieces go, or where i could find out? thanks