I've done the whole super glue thing, but for a more permanent/easier fix just go down to your local car parts/hardware store and pick up some metal "clamps." I don't know what they're called but they are metal tabs you put over plastic and the metal hold the screw in place.
For the areas that won't allow a clip to slide over plastic you can super glue the metal to the back of the plastic and screw into it. Sorry I don't have any names and for the vague description.
Jason