Hey Miles, Just wondered if you had any pictures of the tank with lid now?
Also, I was considering the design, if you pushed the height to 2' then do you think that you would need exterior support for the sides, like 2"x2" running up the outside of the legs? Then a pair of 2"x2" cross supports maybe.
Could you even just seal the inside instead of lining it. This would reduce the cost quite a bit, and reduce the chance that a ray could poke through the lining, what do you think?