this is not done yet?
Do you have more plate other than piece you you cut already? Be a lot easier to drill while its still a large sheet, then cut it.
What are you trying to accomplish here anyway? Cant use a washer?
75G; DIY turtle top, Zilla T5/halogen combo, Sunsun 302, Skim350, Aqueon pro, Saftsorb
50G; Aquasun 2xT5HO, Sunsun 302, Aqueon pro, Aquatek CO2 reg, UP aqua atomizer, Saftsorb