In my ongoing restoration of my new to me 12/86 manufactured C10, have been currently involved in re-assembly of left hand mirror articulation. The right appears to be a single articulation version and a better design needing no repair. I could not get the stock parts on left mirror's two articulations tight enough to articulate in all directions. Any reverse direction of movement in a articulation would back off locking nut supplied by Kawasaki due to play in the double "D" design of pivot bolts. Frustrating to say the least. My simple solution was to replace the original nuts with hardware store steel locking nuts. This gave much finer 'Tune" capability and no backing off on reverse direction movements. A Nylock nut might work also but only the full steel nuts were available to me. These worked excellently! Also of note the rubber gaiter seems to have expanded with age as well. Careful gluing of it into its groves with silicon adhesive and temporary painters tape applied one side/one end at a time over two nights seemed to work well. This glue pulls readily from rubber parts for next dis-assembly. The glue cleaned up well and is not noticeable from outside at all. Note also this repair did require removal of glass to get at the nut behind. Careful application of a screw driver, starting at drain hole, split mirror nacelle readily. The mirror trim ring was re-glued with same silicon used sparingly and held by painters tape overnight. Mirror now is fully functional with no compromises in repair thankfully. Looks good, works better.