rotaryaddict55

I have a 1990 rx7 convertible. The glass mirror in the housing is shaking when I drive from vibration. The screws that hold the mirror on the back side have come loose. I was able to unscrew them when I turned the mirror glass towards the window to get to them in the housing but now I cannot re screw them in because in order for me to get to them and connect the mirror glass has to be turned inward towards driver side but than the housing the holds the mirror isnt connected close enough to re screw them in . Is there a process for removing the glass so I can reattach the screws to the inside housing than put the mirror back on ? I am at a loss and figure someone has done this before and knows the steps to do it correctly without breaking something.
Thanks so much
David