I have to believe the bolt holes for the latch are already there behind the carpet. But that latch is only for stowing the panel if your not using it. I've never folded mine up as I carry stuff under there all the time.
The only piece you really need is the storage bin itself. It attaches by a pin on each side that goes into the lower seat support(??) not sure what it's called but
if you look at this pic its where the red circle is , 1 on each side. Make sure you have a small round hole here for the pin to go into. That's the only thing that holds the storage bin in place.
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