My New Display Cages from River Bend Reptiles

Flexwatt for sure and I know how brutal Indiana winters can be (unless they have their own 80f room) I would also install a radiant heat panel in there to help with inside temps, probably the 80 watt. I have the 40 watt in my 30" and its fine and the 80 watt in the 48". It's controlled by a thermostat so it's nice to have the 80 watts if needed.

http://www.reptilebasics.com/rbi-radiant-heat-panels

Correction....since you have 3 you could go with the 40watt's, the flexwatt on the one above will help with heat on the lower one and the middle one will be warmer.

Funny thing is they do practically have their own room with high temps. We live in a 2 story 2200 sq ft house and there is only one thermostat to control both floors and that's on the first floor. So it is Always hotter upstairs.