When I pulled my clam to replace the radiator I found the lower posts on each side were broken. Not sure if it was the PO that broke them or if it is just a bad design. The way I fixed it was to grind what was left of the post flat then drill a small hole in it. A #4/#6 screw with a few washers allowed me to tighten it back on to where it feels secure and fits flush with the clam.
cool - they are $63 each per light, and as long as they still light up - i'm in no hurry to replace them. Both my lower posts in the front are gone too. I'll check the rears this winter. Thanks for the work around.