Step By Step Mixing: How to Create Great Mixes Using Only 5 Plug-ins

You don’t want to drown out the vocal because it’s the most important part of the song, and you also don’t want the guitar crowding out the vocals in the center of the mix.

panning the guitars out of the center is a good way to make room for the vocal.

doubled vocal, panning each vocal track -10 and +10 will move them slightly out of the center and free up some room for the guitar.