I'm just beginning to build a new tank, on a cheaper budget and with somewhat smaller ambitions than our 90 gal tank on the peninsula. I've got a nice 40 breeder display and I'm installing my own low-profile overflow. I selected the Eshopps Eclipse (Medium) overflow - which has a low profile overflow in the display and an external overflow with 2x 1" drains (which I'll run as a Herbie setup). It turns out the kit also includes a 1.5" diamond hole saw. So I bought a 3/4" bulkhead diamond hole saw, a drill guide and did it myself tonight. I drilled two 3/4" return bulkheads and one 1.5" main bulkhead for the external overflow: I'm glad I had the chance to drill my own tank for the first time, it went well and wasn't that bad.