Where are most of you mounting an interior rearview mirror? Actually into the hardtop above the window, onto the glass, or on the dash?

I purchased a Hagan Fattie Rearview Mirror to match the side mirrors and the bracket really doesn't allow for the proper angle for mounting into the hardtop. So other options are to mount onto the window, which would work, but will obstruct a portion of an (already limited view) front window. There is also the dash, which would eliminate the need for a second mirror for the roadster windshield, but (to me) really seems to clutter the top of an extremely clean dash.

Would like your thoughts on this.

Thanks