I use 11" Flexwatt, taped to bottom of PVC cage with foil (air duct aka HVAC) tape at the back half of the enclosure. Controlled with VE-300. 2 to 2 1/2 bricks of coconut husk for substrate works well although
The probe is taped outside the heat tape so the tape sits flat against the bottom of enclosure.
It's not AP but similar. For lighting, I bought a cheap battery-operated 'glow stick' flashlight that has a variety of colours, something like this:
http://www.amazon.com/Life-Gear-Mult.../dp/B004D33ONK
I use it with the red light to see inside for a few minutes when changing the water every day.
The enclosure sits on the ground so I put down some Reflectix for padding and noise/vibration insulation.