Yeah, it is a bit confusing the way the section-paragraph numbers overlap with section-page numbers.
It appears that you need to push the outer bezel back toward the motherboard, bringing the front-panel assembly out the front along with the motherboard. I'm looking at my 3478 right now and that looks like it'd work since, as you said, the bosses block the bezel from going out the front. Yes, steps n. and o. make sense now, after seeing the arrangement on the chassis.