yank off the c-pillars, unpop the sidepanels, cant remove them tho, you cna wiggle around and maneuver the deck around the side panels. the sides will be held by some clipse hidden by teh backseats, they will have to be folded down anyways.
if you cant wiggle the rear deck around the sidepanels after unpoping them, youll have to remove one side fully. it sucks, but heres how you do it
take off the rear seatbacks, there is a screw on teh hinge where the small and large backseat comes together. the backs will come right out.
remove the seat itself, there is a single bolt there revealed by teh seatbacks gone holding the seat in.
above teh "oh s**t" handles in the back, there will be a small panel cover, holding a screw, pull that
youll see the piece that holds in teh sidepanel covered up by the seat, youll have to pop that out
from here (i havent had those panels in my car for 9 months, forgive me if i am missing something, this si a general idea) youll have to see what else is holding the panel in place. you might have to pull off yoru door sils, they pop stright up and out, you might have take off teh seatbelt s, its a 14 mm bolt holding in the belt, youll have to remove the whole rail, due ot the way honda designed it, you cant just unscrew one on each side.
the panel form here should jsut be held in mby clips, and cna pop it right out.
but you cna see why its far better if you can maneuver that rear deck out without having to remove the sidepanels, cause you can leave your seats in that way, cn leave in teh side panels, teh door sils, the seatbelts, all this crap thats in the way. just to change out speakers!