Jeff,
Here is what I've got for you. I was mistaken about the clamp with J-nut, that is for the door harness (on cars that have door harnesses) to keep the harness away from the door glass. What my mirror has is a round, split plastic loom clip that has a arrowhead which plugs into a hole in the door shell (from the inside the shell) that is at the top of the shell right even with the leading edge of the remote mirror base (the upper part not the flanged bottom). Guess there were two types of clips as I see the kind we were speaking of initially is shown on WCCC's site. So one or the other attaches where I have described. The area I am speaking of is what the door panel lays up against when installed. Hope this makes sense, let me know if you need further clarification.
Regards,
Bob