You might have to mess with the lighting a bit, but it shouldn't pose that much of an issue. If your beardie likes climbing you can just mount the lights as normal at the top of the viv and give him a nice basking spot that's near enough to the lights and the UV, then he can go lower if he gets too cold. But then you might find he is too lazy to bother going to the basking spot (this is what my bf found when he got a new viv, his female didn't like to climb all that way in the morning so he'd have to put her up there to bask when she woke up).
Alternatively, you could get a nice big MVB in that tank, the higher powered ones might even be enough to heat the whole thing too, and you'd have the height to be able to mount it the right distance away from the basking platform, and plenty of space for other furniture and stuff in there.
If you wanted to go the traditional lighting route, you can get pendant light fittings for regular household bulbs that you can attach to the top of the viv and then adjust the drop to be whatever you want so you can get the light the right distance away from the basking area. If you get the under the cabinet type UV mounts, you can just mount it to the back wall of the enclosure, or if you get the arcadia style UV controller where the ballast is a separate unit, you can just put 2 hooks into the ceiling of the tank and then adjust the height of the lamp to get it where you want it.
Personally I'd go with whatever enclosure gave the greatest floor space and about 2 foot high (unless you want to use an MVB), unless your beardie likes to climb, in which case I'd give him the extra height.
