I'll try to post a pic tomorrow. Heres how my setup works:
I have a glass canopy, this one specifically-
http://www.drsfostersmith.com/produc...8&pcatid=13818
I have a 30" current light fixture that has rubber feet on the bottom, which sits on the edges of the tank so that it isnt actually on the glass canopy. I also have my old light fixture, which isnt as wide, sitting on the front part of the canopy, the part that lifts up to feed the fish. When I feed the fish I just set the smaller fixture on top of the other one.
If you buy a new fixture just make sure that its the same length as your aquarium and it wont sit on the glass. Although even if it does sit on the glass it probably wont hurt anything, as long as it isnt too heavy.
When you buy a glass canopy just find one that has a back portion that is big enough for the strip light your using, and there should be enough room for the door to open. For example, the canopy I linked to has a 6.5" back portion, and my main light fixture is smaller than that.
Again, Ill try to post some pics tomorrow..