Rally mirror repair

[Darius]

How does one get the broken mirror out to replace it? I have the replacement glass but I am not so sure about just starting to pry the old one out.
I have heard heating the old to release the glue works.
One of the things I want to try is to fabricate a remote adjust passenger side mirror. I have a 76 Cordoba one that has a long enough cable to reach the driver side so I thought what the heck. The glass is broken so that needs to be changed no matter what.
How do you get the entire glass mounting plate out?
Thanks for any input!

 

[RedFish]

Round or bullet shape housing ? Either way you will need a second remote mirror since the parts inside are all different.
There is one screw installed through the base that holds the base on and holds the mirror support post in place.