UVB lights are effective up to 12 inches away. If you have a screen lid, this could impact the distance as well, as screen tops will filter some of the UV light. I would say the closest you can put the light is 6 inches to be safe, and the farthest you can put the light is 9 inches (if you have a screen top), and up to 12 inches (if you don't have a screen top).
I'm not sure about mounting materials for the basking platform. They do sell hammocks that I know beardies love with suction cups to attach to the sides (if you have a solid sided tank); I would be afraid of putting anything really heavy up high, because if it falls down it could squish your beardie, even if he happened to be basking at the time.
Jungle vines would be fine, if you have a baby. Then again, once he gets adult sized he won't be as active so they could still be great decoration. =)
Good luck!