Reorganized so the bottom plate is the structural foundation and the chassis ("cover") is purely cosmetic. Cover comes off without tools, exposing all internals at once. * Speaker mounts to four tall posts on the bottom plate (60 mm M3 pattern), with self-tap pilots at the post tops. No more screw holes through the cover's top panel. Foam sealing, if it turns out to be needed, becomes a foam donut on top of the speaker frame compressed against the cover underside during assembly. * USB cable routes internally. The connector lives on the Atom inside the chamber; cable threads through a printed strain-relief tunnel a few cm in front of the back wall and exits through a small notch at the bottom of the back wall, matched by a notch in the plate's back edge so the exit sits flush with the bottom of the unit. * Cover retention is snap-fit. Four tabs on the plate carry hemi- spherical bumps that catch in detent recesses on the chassis inner walls. M3 screws and bosses are gone. Post height, cable diameter, and snap-bump diameter are param-tunable guesses to be dialed in after a test print. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>