I was just looking at the pics of your setup again, and it looks like you only coverd less then a third of the lid on the left. If you cover it all up and just leave room for the light on the right, you will find it much easier to maintain the proper temps and humiditys your monitor needs. Better yet, cover the whole top with a sheet of plywood and mount the light on the inside. Another good idea would be to line the back and sides with something climbable like a bunch of virgin cork flats. It will increase the amount of usable area for your monitor since he will be able to climb on it every which way and give him plenty of additional tight hiding areas between the back of the cork and the glass.