I wouldn't worry myself about getting the holes off of their proper location as they're only getting larger by 1/16" and the bit will follow the existing hole. I'd probably do it with a hand drill.
But you're the guy on site. I'm glad you got it done to your satisfaction.

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.