difference in 54 truck/car spindles

Just bought a 54 chevy truck axle, for my 55 chevy gasser project. Can some one tell me the difference between the truck and car spindles spindles? Can I run car drums on truck spindles? If not, will drums fit on the speedway spindles.
Thanks all, for any help.
Chris

 

You can run car hubs on the 1/2-ton truck spindles. You have to mix and match car and truck bearings. I think you use the car inner bearing and truck outer, but it could be the other way around.

 

The backing plate bolt spacing is different from car/truck.