Crank pulley issues

[Pete_89T2]

Just when you think life is good and everything is working perfectly on your rotary rocket, the rotary gods smite you with a real WTF problem... Behold:



After taking the car out for a spin yesterday, I pull into the garage and notice this loud regular knocking sound coming from the area of the belts. I'm thinking a loose belt or failing bearings on the water pump, alternator, PS, AC or the idler pulleys. First I removed the PS belt, then the AC belt and let the car idle to see if the sound would change. It didn't, so then I removed the alternator belts (have a dual pulley because no air pump), and manually inspect the alternator & water pump. Spin both and both bearings spin nice & free with no excessive play. Then I remove the fan to see if perhaps it's loose; no issues there. Then I pull the under tray out to get a closer look at the main pulleys, and two very rusty and broken M6 studs drop out... As seen in the pictures, 3 of the 4 M6 bolts snapped within the crank boss, and backed themselves out, so I only had 1 M6 bolt holding all the pulleys to the crank, hence the noise. The 4th bolt snapped during removal.

So now the problem is how to get the pulley boss off the crank with the engine in the car, so I can get the remains of those studs out and re-tap the holes as needed for new bolts. Any good ideas? I know that main crank bolt is on there good, and probably has permanent thread lock on it from when the short block was built. Figured I'll pick up the flywheel locker tool, and then get the bolt loose with a big ass breaker bar or a rented impact wrench. I know that for the FC, you're also supposed to keep the clutch depressed with something when you crack the main pulley bolt loose to prevent the Torrington bearings to fall loose when you do this. Sound like a plan?