John,
DUH, you noted it is a '53...I missed that. The turn signal unit should be capable of doing what you want, but as you describe it, it sure isn't wired properly. Could someone have hooked it up wrong? It should have 8 or 9 wires coming out of the unit.
I don't know if GMC had a factory turn signal device installed under the steering wheel integral with the column.
Stuart
