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?
55g, diy turtle top, Zilla T5/halogen combo, 2-Sunsun 302, Skim350
29g, Aquasun 2xT5HO, Biowheel 200, Aquatek CO2
15g, Green Element LED, Whisper 15, Aquatek CO2