I agree with the idea of using the Dremel sander (or, even better, the purfling ring). The M6, if I'm not mistaken, has laminated mahogany sides. From my own experience cutting a hole for a Fishman "barn door" on my laminated Seagull, it's very hard to prevent the inner laminate layers from splintering to some extent when cutting, whether using an X-Acto knife or other cutting tool or file.
While that may be fine when installing a barn door, it's not so nice when doing the opposite. Because you don't have solid wood, the port is always going to look (and feel) somewhat unfinished.
Can you perhaps cut the center electronics out of the Micro EQ you removed, and reinstall the brass outer ring?
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- - JM
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