An open table will not work.
Itll be nearly impossible and will require lots of time.
Search "closed chamber" enclosures.
They hold in heat and humidity and will make your life much easier.
I'd also get rid of the moss. Redfoot will definitely try to eat it.
That would depend on the size and height of your enclosure. But because closed chambers are easier to keep warm, maybe a 50 watt CHE?
You can drill holes in your plexi lid and mount your Florescent UV and CHE to the underside.
Hinges held on with silicone aquarium glue are what I use.