My two favorite guns for squirrel hunting: Is my 22lr, scope sighted, Yonkers Kimber Classic bolt rifle, and my rear leaf iron sighted Winchester 1300, black laminated stocked, 12 gauge pump turkey shotgun.
I prefer using 22 long rifle subsonic ammo...because the muzzle report spooks the squirrels less.
But on public hunting lands...I feel that shotguns are safer to use on squirrels than a rifle.
I've giving up using #6 shot for squirrels, and now prefer the #5's.
If you can afford using 3" magnum turkey loads for squirrels...I do not feel that you are overgunned by using them.
Amplified hearing protection for squirrel hunting is a plus for detecting squirrels...not to mention your ears.
Gray and mountain fox squirrel calls do work...
Lightly pan fry them...then throw them in a pressure cooker along with your favorite recipe --- Ooowee...I guarantee.
Good luck...