Originally Posted by TBUChevy
I have also seen people ruin a good sealing surface when the drill bit jumped.
That is a good point, but wouldn't be an issue with a timing cover seal as the sealing surface is laying on the workbench (on the balancer). A light tap with a center punch helps keep the drill in position.

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.