I also don't know if I should remove the metal bezel and reattach it from the outside. I don't have any way of making those narrow slits.
You probably don't want to do that.
My first reaction to the glue idea is it would get gooey, though I was thinking more like 10 years down the road . You idea might work well with contact paper, but that will also get pretty gooey.
I've got an LCD display (16x2) that I got from SparkFun (the LCD-09069) and can't find an enclosure. I contacted someone at Hammond Mfg and they indicated that they were capable of custom routing a faceplate for any of their boxes but the costs would be about $2/box with $175 setup fee and 25 box minimum.. I'm thinking that a good sharp exacto/utility knife and good bezel might be about right. Although the method to mount the LCD is still not clear to me