Pulled the engine two years ago for a total rebuild so I'm sure it is not tapped. I'm aware of the three hub bolts. The main reason I didn't decide to do the extra pulley in the first place was fear that without the crank bolt the extra pulley and the extra torque might work the balancer off the tapered shaft. BTW, where do you find an extra pulley? The extras I got laying around the shop are for a V8 and the holes don't line up. Thanks