My car was missing the stock speaker grills and frames. The someone already modeled the speaker frame/spacer and has it posted on Thingiverse. I used that and modeled this snap on grill. Time will tell if it needs any improvment I've only done very basic testing.
85.5 Speaker Grill
Real world install using infinity reference 4.5's. I cut "boom mat" speaker baffles to fit the spacer, screwed the infinities down as much as possible and snapped the grills on. Sound quality is pretty good.
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