Anyone seen a pin (brace?) like this on a 1965-67 interior mirror?

[Larry Brooks]

Anyone seen a pin (brace?) like this on a 1965-67 interior mirror?
A friend and I bought a good sized hoard of early 356, 911 and 912 parts recently. It had been stored out of sight in a large attic for over 40 years. It included many NOS parts and a lot of light use used pieces since most of it was accumulated in the 70's. One of the early mirrors has a brass pin on the back. Only thing I can think of is that maybe it had a rubber cup on it that braced the mirror against the windshield?

[Mike Wilson]

Looks like an owner-installed item. The tip of the brass rod doesn't look machined.

Mike