do a dry fit with the neck and bridge,
mark a centre line
and ensure by scale length and measurements are correct for it's position.
If all is fine, and it should be , I'd drill the bridge holes.
Just me, but I'd do it before finishing because: You are not risking your finish when you drill, easier to fill/repair/hide if you made a mistake.
Dont forget the hole for the bridge ground, stick some wire through before you finally install the bridge.
Enjoy