Crank sensor replacement on a 3300, is it hard?

I've got a 1990 Olds Cutlass Cruiser wagon sitting in my yard that I'm considering putting back on the road, but at the moment it's not running. I replaced the ignition module and coil packs a few months ago and the car was still running rough so I looked under the hood and the wires off the back of the crank sensor were jiggling, so I grabbed them and the sensor pulled right out! I'd like to get it running again before I decide if it's worth sinking any more money into. What tools do I need to replace the crank sensor? I understand I will need an impact gun and a harmonic balancer puller. I believe I can get ahold of these tools from my dad. I'll have to order the crank sensor clearence tool from NAPA before I attaempt this. What are the steps in replacing the sensor? How long of a job is it? Is itvery difficult?