Help with my Harmonic Balancer

What am I missing...???

Trying to remove the Harmonic Balancer off my Olds 403 V8...

The manual says it should have been torqued to 310 Ft-Lbs...

I have laid into it with well over 400 and nothing....

This thing is not left hand threaded, right???

I have sprayed the "area" with penetrating fluid...

Whats next, a bigger cheater pipe..?? how about a torch on the bolt head...??? then catch it after it cools...???

I don't want to shear the bolt off...!!!

Help..!!!

Is the motor still in the car?
I use a 5ft pipe(fence post) on the breaker bar and have always got it that way.