[kc8adu]

get the glass spotlessly clean along with the crt face.
i use tiny rubber self adhesive feet about 1/4 tall and diameter.
i place 6 at the edge equally spaced to support the safety glass while the silicone cures.
support the tube in a plastic trashcan that will hold it by the funnel but not allow the neck to bottom out.
apply the clear silicone in a bead a tiny bit taller than the bumpers at the outside edge.
carefully place the safety glass without sliding .
this means you get on shot as moving more than say 1/2 in will cause smears that will show outside the bezel.
allow to cure 24 hrs.