Putting an external overflow on a prebuilt tank

[blacknife]

Mark, how do you propose notching it?
most of what I have read says leaving corners in any structural wall on glass is not good.


might have to look into one of those diamond edged grinders to go with the few sizes of glass hole saws i already have and slot near the top similar to dez's. That would probably look cleaner than the small internal overflow i was planing ported to external for the plumbing..