454 Harmonic balancer removal help?

[93FatBottom]

I'm trying to remove the harmonic balancer off my 454 to get to the timing cover to do a new set, but I can't get the bolt to budge. With the breaker bar, it spins the crank, with the air ratchet, it bogs down and tries to spin the crank. I'm worried that the impact wrench will either snap the bolt head off or it'll just spin the crank at a ridiculous speed. The motor has no flex plate on it, so theres nothing to stop it from spinning, I can't find anywhere locally for a piston stop, and I have the pan off and the motor upside down, I'm not planning on pulling the motor off the stand again until I have it buttoned back up and degreased and ready for some paint. Is there anything I can do here short of pulling the motor off the stand and re-attaching the flex plate? I've been scouring the internet all night for some kind of trick to it and nothings popping up except for tricks involving the flex plate. My friend told me to put the spark plugs back in and try it again, but I highly down that will do much good, or am I wrong? I'd appreciate any advice, I'm looking to have the balancer removed and the timing chain done before I have to go to work tomorrow night.

If anyone has any advice on prepping for paint, it would help a lot! I have some Gunk Engine Degreaser, some Simple Green, and oven cleaner. I also have a wire wheel. I dont want to pressure wash it because of all the openings, I just want to get the motor stripped clean off so I can rattle can her nice and pretty. I'm doing Chevy Orange and Flat aluminum Rustoleum. Should I paint before or after I pull the freeze plugs out for replacement?

Thanks guys!