Is this mirror joint suppsed to be moveable?

I am trying to fit a blend mount for my V1 to my Prius rear view mirror stalk.

I am told by the owner of Blend Mount that the ball joint closest to the windshield should be moveable, just like the joint on the back of the rear view mirror itself. But it won't budge, I am afraid to put too much stress on it for fear of breaking it off the glass or breaking the glass itself.

I have successfully used this exact same mount on my other Prius and it worked fine, it IS the correct mount for this vehicle.
Why doesn't the bleeding thing move. I can't imagine it's from lack of use but maybe it is. I hate to spray anything onto/into it because it will make a mess running down the glass.

How can I loosen the silly thing so it moves as it should? I'd love to whack it with a rubber mallet but I am trying to resist the temptation! lol

Thanks "ES"

 

Thanks I will have to look for that set screw..tough for me to bend due to two spinal fusions. At least I was right in thinking it would move. on my other Prius the blend mount worked fine but due to this thing being tight I can't get the mount leveled out.

Regards, 'ES'

 

Sorry guys but I see no set screw that is holding the stalk to the plate on the windshield. It's impossibly tight otherwise with no hope of moving it upward to get it off the glass.
Not sure how to proceed with this one without messing it up.

Thanks,

"ES"

 

Thanks for the video link,, looks like this one was made during an earthquake! But in spite of all the jiggling around I get the idea and am off to try it now!

 

Yes I was able to remove the mirror and install the blend mount to the mirror when it was off the car.
The ball joint closest to the mirror was almost impossible to move even with generous applications of silicone spray,

How did I get the mirror off the windshield you ask?...

I simply gave it an upward whack with the heel of my hand and it came right off, no need to fool around with a pick and try and take the tension off the 2 spring clips that hold it on.

The photo shows the metal springs and the ball ( almost dead center ) of the almost impossible to move joint. I centered it as best I could and for some reason everything is in line and the V1 is straight and level! Great stuff!

Thanks again,

"ES"