I'm working on a PRS-Q1 kit and it doesn't come pre-drilled for the bridge. It's taken weeks to get the courage up to drill into this thing since I know how crucial bridge placement is to the sound of the instrument.

I was pretty sure that I saw in a video or read somewhere that a 7/16" bit was required. While at the hardware store, I brought the bridge along and tried to measure by holding the bit up to the pieces. Thought I might be OK with a 3/8" bit, so I went with that. And also because they didn't seem to have any bradpoints at 7/16". MISTAKE!

So I get home and drill out the holes only to find out that the 3/8" bit is too small. So now I have the need to widen these holes to 7/16". How? I have now acquired a 7/16" bit. However, because this is the bridge, I need these holes to be near perfectly on center. Otherwise the bridge and tailpiece won't fit right. I'm not sure I trust myself to eyeball this.

Two ideas I've had so far:

1). Fill the holes with either wood, glue, or a combination of the two. Then it's just a matter of re-measuring and redrilling. Any material added would just get drilled out anyways. Problem is I don't have spare wood really laying around so it would probably need to be all glue (Titebond II). Is that OK?

2). Measure the difference in diameter, divide by 2, mark out that far from the existing edge of the hole in 4 directions. Problem here is I don't have a caliper or know if I can precise enough without one. The smallest markings on the rulers I have now are cm. Maybe just buy a caliper?

Tell me the best way to remedy this situation!