the flexwatt gets taped directly to the bottom of the cage the cage is thick but the flexwatt heats it just fine unless you have a really cold room then you might need to add a radiant heat panel i would start with the flexwatt and see what your temps are then if needed add a radiant heat panel. when i ordered my enclosure from ap they installed the screws for the light. all you need to do is just add the light to your cart and it will come with the screws in place and you just run the cord through the supplied hole and place it on the screws and slide it to the side and your done.
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why dont you post where you live maybe there is a local herp club or a forum member that wouldnt mind showing you their enclosure or giving you some hands on help to get you started.
http://ball-pythons.net/forums/showt...With-Pictures! as already mentioned earlier this is a real helpfull post and should cover most of the basic questions that you need answered