by the looks of it either the wheel came off or a low pole was hit while driving forward, What it needs is a pull forward before you start any hammering or pick baring from the back side, try getting a body clamp and a come-a-long and pull the edge area forward while pry baring or picking and lightly hammering the buckle while the pressure is on it with the come-a-long. Not a bad idea to get a pro to look at it.
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