Another thing to try is some super glue in the wood behind the plates. If the wood is not oil soaked it will help strengthen it, if it is oil soaked the glass bedding won't stick either, so you'll need to degrease it anyway. I like super glue because it is thin as water (not bulky like glass) and soaks in great, cleanup is easier - just wipe off any extra with acetone, and you don't have to mix it like epoxy. It really is "super"! - sorry couldn't help myself.
Bryndon