Easiest way is an air impact gun.
If you don't have one, you'll need to do this..
get a long breaker bar..
and then take all the plugs out of the motor.
Get waxed twine or string, and a lot of it.
Pick a cylinder, any cylinder, one that's easy to get to.
You're going to rotate the motor by hand until you see a piston moving UPWARDS. you don't want it to goto the top, but maybe halfway.
Fill the cylinder with the string. this why you want like a waxed string, any regular string that leaves strings wouldn't be bad, but why bother?
so stuff the string into the cylider, pack it tight and make sure you can pull it out later...
get your breaker bar ready and start tugging counterclockwise on the crank bolt. you have a piston that can NOT move due to the string, so there's nothing to stop you from putting all the muscle you can into breaking the bolt loose.
once you break it loose, do your thing.. when you goto torque the bolt when you put it back on, the string will still hold the piston in place.
Other option.. get a dremel tool with the grinding wheel cutter and cut the sides of the washer off. you will be removing like 40% of the face of the washer and you would be able to break the bolt loose probably with the plugs left in.
you will however, need to buy a new crankshaft bolt.. like $9.