[CKfan]

Hmmm looks like no-one wants a piece of this action (Vin plate issues).

With that said, it is a 99.9% bet the body shop did not weld in the (4) rivet holes where the plates affix (2 top plate, 2 lower of course).

So, just reach behind the B pillar with your hand and feel the push through nubs of the filler they used and there you go. Putty knife it off and use an angled pick to push it through the front.

Good luck.