I would be very cautious with a high heat source on neodesha cages. I had the three foot slant front versions at one time that showed some discoloration due to a heating pad set beneath them. I would not set the heat source on top of the plastic/mesh area. Instead, I have seen sockets mounted inside the cage. You can go to a hardware/home improvement store like Home Depot, etc., and get spotlight mounts. Find one that angles and mount on the side at appropriate hight to provide basking spot with proper temps. I didnt notice my neodeshas holding humiditiy any more than an aquarium with screen top to be honest. I think at that size it with a high heat source it would be hard unless you misted substrates or placed a large water container in the cage on the warm end.