Many thanks to
@abide for test-solving and suggestions for improvement.
hint #1: the plate in the title refers to license plates... license plates will sometimes have the state's nickname on them
hint #2: see if you can find state nicknames in the grid, there are 8 of them (search online as needed for any you are unfamiliar with)
hint #3: they all follow the format "the [something] state" and are symmetrically placed (including 45-A)
hint #4: take the first letters of the states in grid order to spell out a key word
hint #5: there is a wikipedia page on "mountain states," but that is a geographic division and not a state nickname
hint #6: rocky mountain, iron mountain, green mountain, white mountain are all state nicknames, but they are not the meta answer... there is a state that is just "the mountain state"
Thanks.