I am like you, I like the 48-53 gmc fronts and I REALLY like the early 47 1/2 ton gmc front end, I have a bumper here and would love to find another grille, they weigh a ton but I digress..
you will need everything related to the hood, the core support is different as has been mentioned and the hood latch area is two pieces unlike the chevrolet single piece, although my 47 GMC did not have the second piece included and I didnt need it with the s10 swap.
I havent tried using the chevy core support in place of the gmc one but like mentioned the radiator mounts INSIDE the core support on a GMC instead of mounted to the back of it like a chevy, the GMC engines were longer and needed the room for the fan.