how do I replace the right side mirror on a 1986 Chev. Caprice

If there are no screws on the outside of the mirror holding it on, you will have to remove the door panel to get to the screw/nut/bracket holding the mirror on. Look on line at the mirrors for your car and see if the bottom has screws/bolt holes under the flange that fits up to the door. Use a wide small pry bar to pull lose the fasteners to the door skin after removing all the handles and trim pieces to the door panel. Gook luck. It is always a great feeling when you get it done yourself.