I have 2 overhead projectors that blow their bulbs. At $18-20 apiece I don't have the money to experiment with them anymore to figure out why. Has anyone got an idea how to convert one to use something like a standard Halogen or Xenon light? I would also need to keep the fan functional as well since any strong light is going to get very hot. I use them in my fiber art studio to project ideas onto paper for patterns.