Hi Tommy! Welcome to BP.net! :handshake
Nice lookin' snake you got there!
You need to watch both of those temps on your thermometer. Place the whole unit inside the cage on the cool end (I just prop mine up in a corner) and then place the probe on the warm side. Tucked under the warm-side hide is a good idea. You want the temps to be 90-94 on the warm side and 80-84 on the "cool" side.
If you find it difficult to heat sufficiently through the substrate without heating the glass to dangerous temperatures, just reduce the amount of substrate you're using. They only need a thin layer of it to absorb wastes.