The force applied to each bolt will be the same. The spanner wrench actually applies torque to the pulley through the bolts. You have to have both bolts attached to get the pivot points (fulcrums) established to apply the torque. It turns out that equal amounts of force are applied to each bolt.

I would make the handle as long as possible, but keep in mind you still have to get it to the pulley. On my daughter's car I positioned it from underneath.

I did a search for ed c's tool and couldn't find it. Can someone attach a link or picture?

Best of luck and continued success!
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