I have a dome light attached to the screening over the enclosure, with a halogen bulb inside of it. It is on the far right side directly over one of her hide boxes, while there is a second hide box on the opposite end (so one box is being heated by the light and the other is not). The hot spot is a bit warmer than I thought, as the hottest spot is 90 degrees, while the ambient is a bit over 80 (I may need better thermometers, it is hard to get exact unless it is at a round value like 90, as the dials are small and it doesn't list every number. it's about halfway between 70 and 90, so it's approx. 80 give or take a couple degrees).

Since I live in Florida and it doesn't get particularly cold here, that single light has been enough (or so I thought, but since she is vomiting maybe I was wrong).