Rear View Mirror Pad

["Rustproof" <Rustproof@xxxx>]

I am getting ready to affix a new mirror button to my new DMC windshield. The glass arrived with a small foam pad that warns that I should use it when I affix the new button. The rest of the rearward-looking world just sticks the thing directly to the glass with adhesive made for the purpose. Is there a dark secret about DMC glass we should know about? The pad is not self-adhesive and can't be used to actually stick the button on. Has anyone actually used one of these? I would appreciate someone shedding some light on the best way of affixing a mirror to the windshield.
Thanks,
Rustproof
Vin# 1559

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