Adding light/ UVB to my new vision cages

I got a good deal on 2 used vision cages last week and I was curious on a good way to add light. They have a spot for a heat dome lamp which is fine but it doesn't provide even lighting and does leave room for UVB afterwards. There is a recessed part in the middle where it looks like a tube lamp would go but there is no mesh or way for it to shine through unless this is for something else.

http://img.tapatalk.com/d/13/01/24/edu3any4.jpg

http://img.tapatalk.com/d/13/01/24/ge5a9ava.jpg

I saw one where a guy just put a ceramic fixture and put a fluorescent type bulb but I'm afraid of a snake of something getting to it. This may be less of a problem with a lizard. I currently have a boa in one of the 2 cages I bought.

Do people make a cut out in the center and put wire mesh or something? I would like to have it as an option if I get a lizard which needs UVB.