yes schapman...i used 1000 grit before adhesion promoter and primer. i also removed the mirror from the car and removed the glass mirror from the housing, which came out fairly easy.

 

silly Q but how do you remove the mirror casefrom the car to do all that work...and then..how do you remove the actual glass mirror without messing everything up?

 

if you look inside the door at the mirror area,you will see a triangle shape plastic piece that covers the bolts that hold the mirror on. just get you fingers on the edge of it and pull gently and you will see that it just pops right off, i think in 3 places. easy to do. then remove the bolts and unplug the electrical and pull the mirror off with the foam gasket. then with the mirror laying on a towel or something soft,rotatethe mirror all the way in on on end and if you look down inside between the mirror glass and housing you can put a long skinny screwdriver in there and pop the mirror loose from the bracket. its a little hard to tell what it looks like but if you do a search on here, someone had pictures with the mirror glass removed.

 

here miranda..see if this helps.
https://mustangforums.com/m_2588675/tm.htm