There is a tool to lock the flywheel and in my opinion, using it is the best way to do it. I just recently read on here where someone suggested removing one of the bolts from the torque converter/flywheel and installing a long bolt that lock the rotation of the crankshaft down to allow you to loosen/tighten the crank bolt. I have the tool for the M103 engine and w$$ish I had the one for the 617 but am planning on trying the long bolt trick next time I have to tighten one up. Right now I lock em down with a long crow bar and the proper breaker bar/socket on the crank bolt. It takes two people to do it this way. Ya'll should have been out there last time I asked the wife to help with it
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