I have 2 different 57 rear view mirrors,.. and 2 different styles..... but on the style with the circular ball type....I am missing the bracket that is in the inner base...(holds the ball with pressure) I probably have it... just cant remember what it looks like.
A 55-57 T-Bird unit is much different....
Anyone have a pic of what the bracket looks like?
(https://i.imgur.com/gSvPwlL.jpg)
(https://i.imgur.com/IMfkQzf.jpg)
(https://i.imgur.com/xRBLwWy.jpg)
I am following this as I have the same issue. I don't think I had anything inside of mine when I removed it. I am thinking a spring would work but hope to hear from others.
Flat, tear drop shaped piece of metal with a divot to match the ball. It is fastened with a flat head screw through the hole in the base. I've had both styles. The ball style threads match up to a 1961 Thunderbird mirror that is day/night and chrome and is being reproduced. Don't have a picture of the inside. I'd have to remove it from the car and I haven't even got the car out of storage!