Rear fenders on a 51 will they fit?

[PAPA KENT]

Hello guys,a friend of mine picked up a very clean and original 51 chev 3/4t longbox recently and he's looking for used rear fenders,now are the short box fenders interchangeable with the long box fenders on those years? The truck still wears it's original paint and except for the rear fenders it is a very straight truck with no rust through anywhere.the rear fenders have more dings and small dents than he wants to deal with and i have heard mixed comments if they will interchange.

Thanks for your help.
Kent.