Autobahn

I wanted to examine the rear speakers to see if they were amplified Bose or just the same speakers that come with the non-Bose Z. They don't sound very good in either case. If they were non-amplified I was considering swapping them out for better quality 6.5" speakers. I thought there were a series of screws holding the speaker grills on but on closer inspection what I thought were screws seem to be decorative bumps. Anyone have an idea how the rear grills come off before I do something stupid like just trying to pry them off?

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