Hi there, the t5 should be mounted inside since it's a 5.0 [ the only exception would be if the screen had large holes instead of small and the light could be within 7-8" of the dragon ] So mounting under the screen with wire like this :
https://www.beardeddragon.org/media/30028/full
The the next time you order a new bulb you can get the t5 10.0 + put it on top of the screen.
For cage decor I've picked up beautiful half logs + driftwood outside that can fit in my oven, then preheated to 250 + baked for 60-75 minutes depending on wood thickness. Yu can also get nice large basking rocks, those you can just wash with hot , soapy water + rinsed. If you prefer, just get the cage decor at the store [ skip hammocks ] but I like my natural logs from outdoors and what a bonus when they're free.