I agree with the thermostat comment.......it's critical you no the temp of you hot spot.
I would put the hide on the hot spot side of the enclosure. Put your water bowl on the cold side.
Also to minimize your undertank potential overheating....in the short run...I would put some newspaper over the heated tape area and then maybe some substrate on top of that. This will keep a barrier between the snake and the glass. It could be dangerous for your snake to have direct contact with that glass if it is to hot........thus creating burns.
Definitely persue a therostat control system, you may also persue a digital temp guage that also reads humidity. You can keep it located in that area to see what you environment is doing. It's always much more comfortable knowing that you have the right environment for your snake.
Jim