If you're very clever, it probably can be. most of us dont' know what a 50 pontiac box looks like, does the shaft go all the way up to the steering wheel, or does it have a spline and coupler like the 70s-80s GM steering boxes? if it goes all the way up you'll have to cut off and safely spline or otherwise modify the shaft to fit a coupler of some kind.
There's no 'A' in steering column... You will recieve a 'spelling check ticket' in the mail from the Hamb...make all checks payable to Ryan.