First, I drew up a template.
And here it is:
Then, I cut the template out with a jigsaw:
Intonation marks:
All drawn up on the guitar (note: That is not the real center line):
Before routing, I did a trial run on some other wood:
Dry fit after routing:
The masking tape tore up pretty bad during routing. That's why the shape's off, but it works great:
Mounted:
Proof that it all lines up: