[G&R's57GMC]

Humm ‘72 Buick column, the switch should be mounted low on the column . It most likely is pre HEI . I don’t think HEI came out until ‘74 so the switch would be different than the ‘72 switch . The HEI requires a 10 gauge wire so the switch would have to be able to carry the higher current .
Food for thought if your switch doesn’t have a 10 gauge wire feeding it and a 10 gauge wire to the distributor from it then it also won’t have the circuit inside to supply the distributor during crank and run .
But what do I know it’s been 26 years since I retired from the auto repair trade .