They are just alignment pins. Not bolts. Those storage trays are made to be removed. They do not even move when in place and the rear deck lid is closed. I suppose if u wanted them bolted down you could install studs and secure them. I personally remove the one on the passenger side often to access my audio equipment. One holds my amplifier and it doesn't move at all. I suppose if I turned my car over they may move a bit, so if that is a concern I definitely suggest bolting them down.
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