Is it easier to get a fly wheel puller than risking a damage engine. A good flywheel puller are like $25 to $35 and not risking hundreds of dollar in damage..
I've seen multiple crankshafts broken with flywheel pullers. If you are going to use a puller, keep in mind if the flywheel does not move easily with it you could still damage the crank.
Striking the flywheel from the side toward the front of the engine with the handle of a soft handled screw driver seems to work the best for me. Light strikes, spin the flywheel around to even it out and it pops right off.
Also I would suggest getting a pair of vise grips or channel locks that are big enough that you can grip the flywheel from it's diameter, not pinching one side of it. You will be able to apply more torque to the nut by doing so and remove the nut easier.