http://www.parts-express.com/catalog/pd ... 4pec10.pdf
When mounting the speaker, sometimes a T nut,depending on which ones you get, the flange may be wider and stick out past the cutout. From the link it shows many types of T nuts,,hurricane nuts and barrell nuts.
Some have a smaller flange,some have more barbs etc..
These can also be used in the cleats if you mount that way, instead of just screwing the baffle into the cleats.
Just a few ideas you can think about how you want to mount the baffle and speaker. Some people like to put bolts through from the front, and have those to set the speaker on. I don't like that way as much, you have to be real careful when mounting the speaker, not to poke a hole in it,if you drop it, or don't have it all lined up good.
But as the link shows, a bag of those is not much,and can also get the bolts that fit the nut you choose to use.
They also use those for the handle.
Also, another hint would be, if you use these, you can use a black magic marker or paint etc.. to make them dark so they won't show through any grill cloth.
Also depending on what your using for grill cloth, its best to use a dark stain on the baffle,or color stain matching the grill cloth.
That way, its dark behind the grill cloth.
When the stain dries, after you have the speaker hole cut,and mounting nuts pressed tapped in etc.. then you can put on the grill cloth.
HTH
Richie