Oh, okay, I read the compartment part but it didn't really register. Whenever I look these tubs up online I can't find the green version, only the red, which doesn't have the compartment. Hmm. I kind of want the compartment version when I upgrade sometime next year, might do something like you plan to do. But where to find it..... (sorry to distract lol).

The RHP idea sounds fantastic! Maybe you could attach the UTHs to the parts of the tub that do touch the ground??? Hmm. Maybe someone else will pipe up with more ideas for this, because I'm really liking it so far.