1996 Pontiac Bonneville crankshaft pulley

Depends on the pulley you are trying to get off but I have found leaving the belt on and putting pressure on the belt helps

1996 Pontiac Bonneville se. Electrical impact didn't budge the bolt. And how do you safely suggest I do what you are proposing?

If you are trying to get the crank bolt out they are very tight and I use an air inpack gun. You can try to take the inspection cover off the transmission so you can get to the flywheel or the starter out and try to put a pry bar in the teeth of the flywheel to hold it in place and use a breaker bar on the bolt.