55.2-59 Part Recognition

[BBPanel]

Anyone have an idea what vehicle the license plate "frame" might have come from? The bumper is a 55-9 Chevy Panel. The current owner said the original owner could not remember what the "U" shaped piece came from but did say it was flipped 180 deg ("U" facing up) in its original orientation. I don't know how much modification was made to it but it sure fits the bumper profile well.