Yeah I know. Probably to keep water from getting in. I was going to put the drop lens refractor that I kept from the Westinghouse OV-25 I had in this OVW. But I don't know what it will do to the paint if I try peeling off the silicon.
Get a razor blade and slide it underneath the silicone (try to remove the FCO glass first if you can). It's a powdercoat so it shouldn't damage it and besides, it's just the refractor rim. You'll never see it.