Hadn't thought about a plug for the rabbet issue. As I understand it slosjo's issue was with the through hole not the rabbet. I brought up the rabbet issue as another example of spending hours doing something with sandpaper that could have been done in seconds with a router had I known how.
How tight do you need to make the plug so it holds position while you route the rabbet?
Mike
If just increasing the depth or diameter of the faceplate recess, the plug would only need to be snug so long as you have some backing so it doesn't push through, just do it on a nice flat surface and no worries.. All it needs to do is act as a center for the circle jig pin.
I'll have to go back and re-read the issue with the tweeter... I thought the diameter he cut the recess was too small for the faceplate to fit into. If that were the case, the plug would work for that as well.
I used the same technigue to increae the diameter of the through hole in some cabinets I had originally built for the X LS Classics but tha decided to go with the large faceplate Encore kit. Only difference was I glued the plugs in place, once it set up, I recut the through holes to the Encore size which also took out all of the plug

-jay