Don't know about a 57.
A 47-53 for sure, and probably lots of other years, does not come apart. It can be disassembled, but the shaft that the wheel attaches to is part of the same shaft the ball screw is made of.
Pretty much you can remove the steering wheel and that's it unless you take the whole thing apart.
Is this the same construction as a 57?

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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