This doesn’t look like a very active forum, but I wanted to mention that at Resosummit this year Paul Beard gave a talk about setup and maintenance. He described how the bridge and spider want to rotate to the right because of the tension and gage of the strings. When I put on new strings I have always just eye-balled whether the bridge was square. He sells a plastic jig for $35 that shows if the bridge is square and proper distance from the 12th fret. I bought one and tried it on my guitar and sure enough it needed adjustment. It’s easy to just use a small screwdriver to pry that spider back to the left so the bridge comes into square. I have previously noticed how when I use a capo I am compensating by putting it at a slight angle (to the right!). Now I don’t have to do that and full-bar chords seem to be more in tune.
Steve W