It is really not a good idea to rest the fixtures of bulbs or ches on the screen. It is not good to move them around plus it is not very safe. I suggest using a lamp stand so the che stays in place and you can remove the screen without moving any fixtures.

Not seeing your setup I can really only guess with the picture I have created in my head. I would not think the snake would burn its nose but that depends on how hot the screen is really getting. Having a IR Temp gun would be really handy right now.

I am worried about the hotspot the che is creating inside the tank. A che is more like a spot light style heat bulb instead of a flooding style. This means that it has a concentrated beam of heat pounding a spot on the tank floor and can very easily get to hot. Again a IR Temp gun would help make sure this is not happening. You may need to switch to a bulb. I used to have a 40gal in a room that stayed 68. I had a 100W(on a stand with several inches of standoff) on one side and a regular 60w bulb on the other to keep the temps correct. You may also need to do something like that.

Check out these. http://www.amazon.com/Zoo-Med-Reptil...med+lamp+stand
I have used them for several years and they work very well.