My home has enclosed, recessed ceiling fixtures circa the 60's or 70's. They have a metal rim holding in a glass cover plate, and the rim is snug against the ceiling tiles. The rim is all one piece and the glass is tight under the rim. I cannot for the life of me figure out how to open these fixtures and change the bulbs... I was hoping to change out the fixtures before all the bulbs burnt out, but monetary woes have stalled that process. Can anyone out there guide me through the procedure? I wanted to post a picture but they won't let me :(. I'm pretty handy and have most common tools at my disposal. Thanks!