Probably you’ve done it already but I will answer it for other people that might be facing the same problem.
As far I can see there is no guide or tutorial on how to do it.
After removing the speaker and sensor unit you need to very gently remove the plastic bracket/thingy that stands in the way of speaker mesh. It is glued to back of the glass and very fragile.
What I did was heating up top portion of the screen from the front with heat gun. Then I was able to get this thing out by praying it out with plastic tool starting from the left side. Afterwards I pushed the mesh out from the outside. Then the metal tab on the mesh slides downwards out from underneath of the screw thread. And that’s it.
Just be careful to not heat it up too much, otherwise you can melt that plastic bracket.
Hope it helps.