It also goes back to my time where in dealing with bumper numbers a picture isn't always the best way to tell. Folks should also put down what they see cause it is difficult to tell what the center photo has on it.
Helps to know where you got it. That way if it is direct from the govt, we figure the numbers are original. If you got this from another private citizen, I'd say the B131A is made up. Then again, is it a B 131 triangle???
B 131 Infantry is a IL ARNG unit. But again, not knowing where you got it limits those of us that try and decipher such things.