Yes. The bridge is the most important element to position, and that’s already done. The stop bar needs to line up with the saddle slots, but the fore/aft positioning isn’t too vital. Just measured a Les Paul and the stop bar is roughly 4cm back from the bridge. You won’t want it much closer otherwise its hard to get a good string break angle, but it could go back a bit more if you want.

The standard trick of running some string up and down the neck and over the bridge should allow you to line up the stop tail nicely. Better than trying to work out centre lines.