Mac clutch keyway plan B

[Bill Peck]

If I'm unable to find someone to cut a new keyway in my Mac crank  I'm going to try the "lap and torque" method that was discussed in the thread "820 Starter Cup" from February. That thread suggested torque values ranging from 280 in-lbs to 360 in-lbs for a West Bend. What kind of torque should I be putting on that skinny little Mac clutch nut? The last thing I want to do is break the nut. The memory of Scott working for an hour or more to remove a broken nut at Thompson is way too fresh in my mind!