Just an update, I ordered this mirror from Classic industries https://www.classicindustries.com/pr...s/3914753.html
I asked Craig Maiorana about it and he said that it was tight and should stay in place. He was right. I launched my car at 7000 RPMs on slicks and ran it through at 117 MPH at Beech Bend and the mirror never moved. I can recommend this mirror.

I bought a pair of reproduction mirrors for our Z from Heartbeat 3 years ago. Wife has been daily driving it since and they are just fine.

Last year when I restored my fathers GTO, he bought a pair of reproduction mirrors from Classic Industries. They've also been perfect and never budged on this pass.

https://youtu.be/Ah_LjF_Sxow

I had trouble with mine, even after taking a punch and roughing up the ball. I drilled about 3 of the punch holes deeper and put some blue loctite on it and it hasnt moved. I havent messed with it either!!

Mine held for a while with the punch marks, but just cleaning it got it loose again. I think this new one is going to work fine.