BLUE TONGUE SKINKS

Hi all,
I've had my BTS for a little over a month now and am going to be upgrading him to a 4'x2' pvc cage (I am going to order one for pickup in early September at a local show). I am going to be ordering his cage from CSerpents, but had a few questions for you guys before I email Chris for a quote. I can't decide at this point between a 2'x4' x 1' high cage with a mesh hole on the top (to place heat lamp on top of cage) and a taller cage with internal heating. I'm also not sure about what height of substrate dam and what door style would work best... I prefer sliding glass with snakes, but I'm thinking my BTS would easily get dirt in the track of a sliding door... All this said, I have some questions for you guys to help me determine what to ask for in my quote.

1. Do you use a single piece drop-down door, a double-piece drop down door, or sliding door and why?

2. What height of substrate dam do you use?

3. For those using internally-placed heat lights (and /or fluorescent lighting) what height cage do you use and do you use anything to cover the bulb (mesh cage, etc.)?

Thanks so much for your help folks!

I use a sliding doors because IMO because I build my own to save money and to me it seems like the easiest option so its more of a preference

for a substrate lip I use 2 inches and make the substrate vary in height around the tank and it seems to do the job and keep stuff out of the track

for internal lights people say to have at least a 12" barrier between your substrate and bulbs to reduce the risk of harm to the animal and fires, but wattage of the bulb also matters so keep that in mind. IMO if you can cover your bulbs with mesh I would just to be safe