Don't worry about lighting at all as Royals dont need it. If you go for a wooden viv. then i think youd be better off with a ceramic bulb at one end of the viv attached to a thermostat for heating. Dont forget a guard to fit round the bulb so that the snake cant burn itself. Your other option is to use a plastic Really Useful box with heat mat and thermostat under the box: this is better for hatchlings.