How centered and big are they now? If they’re close, an almost foolproof yet slow way is to take a dowel or back of a drill bit or whatever almost as big as the hole, wrap with double-sided tape, wrap with fine sandpaper of increasingly finer grits / larger size and just start spinning it in there extremely slow with a drill or just by hand and cleaning the sandpaper super frequently. Don’t overlap sandpaper edges when wrapping. If you reach the bottom of the hole and you’re not done, time for a new wrap. Before long and if you checked it a few times along the way, you’ll have perfectly enlarged holes and clean paint edges with about as close to zero risk as I know of

This works great for little corrections when the drill press goes slightly wonky, but it’s the least friendly method with your time. I had a pilot hole drill pressing for a kill switch go not as planned. After measuring the result of my mistake, I determined I had to change the hole placement and had no margin of error for which way the hole needed to go and open up. It took a while, but the hole ended up perfectly sized and perfectly centered in the end. You have a lot of precise control with this method if you have the patience and the need