John,
You didn't say if the 47 was a 3100 or a 3600.
If they are both 3600's then the rear wheel cylinders should interchange.
A lot of parts catalogs list the same rear wheel cyl. for '46 to '52.
3600's kept huck brakes through 1952. 3100's had huck brakes through '50.
Also...3600's through '52 and 3100's through '50 used the same front brakes (huck style) so those parts should also interchange except for the drums.
