Yo Pete,
The big problem is your canopy wasn't sanded enough before it was glued on last
time. I mask it off and then sand the hell out of the 20 mm area where the
epoxy glue and cotton flox will be applied. I sand with 40 grit till all the
shiny is gone and then blow it off and glue her on. A few wood screws may be
necessary to keep it in place, but I remove them before the epoxy gets rock
hard.

If it is that loose, can you take it completely off and start over? If not, you
need to get some ruffage up there in between the glass and the frame. If that's
not possible, you can drill some holes and let the epoxy ooze out through these
holes. That might be enough to keep her down.

Mask everything off, its much easier than removing fingerprints etched in
epoxy.
JJ Sinclair