As pointed out by triplep, the drums are attached to the hub by serrated studs and in addition, they are swedged on. The only way to get the drum off is to remove them as an assembly.

Have you backed off of the adjusting wheel cylinders on the front brakes (also pointed out by triplep)?

I’m linking sections of a 47 Chevrolet Truck Shop Manual which should be similar to yours, so you have an idea of what your dealing with. Also linked the adjustment procedure so you know what needs to be loosened.

http://chevy.oldcarmanualproject.com/shop/1947truck/47ctsm0304.htm

http://chevy.oldcarmanualproject.com/shop/1947truck/47ctsm0514.htm

http://chevy.oldcarmanualproject.com/shop/1947truck/47ctsm0506.htm

Last edited by Phak1; 04/27/2021 1:46 PM.
Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
Project Journals
Stovebolt Gallery Forum