Peter Cousins G4NJJ suggests that to get a tidy speaker grill on your EF01 or other enclosure you should have a rummage in the kitchen utensil drawer.
You may find the perfect template. Peter used a plastic sifter lid as the holes were the size he wanted.
He drew a center line where he wanted it positioned, lined up the template, drilled one hole on the outer circle and inserted a nut and bolt, drilled a hole at the opposite end of the template, inserted a nut and bolt, and then drilled out the rest of holes in perfect place. Hot glue allowed the speaker to be placed on the underside of the lid of the enclosure. Done!
Oh and in case you wanted another idea for the template … And just make sure the XYL is not aware of your minor “alterations” to essential kitchen equipment!
And if you want a variant on this theme of making a speaker grill look real classy, check out Glenn VK3YY’s website for a ham shack alternative that won’t get you in so much trouble with the XYL: https://vk3yy.wordpress.com/2017/01/22/bitx40-v3-and-raduino/