I took down a barn door in a bedroom because it was only 80” and the previous owner hung it too low (should used a 94”or 96” door too). My problem is removing the support board. See pics. This is what the barn door rod was attached too. This board is somehow attached to the wall/drywall/stud and I have no idea how. I don’t see any screws and it’s on there good. How do I remove this thing?