Picking only three seems like a disservice to many wonderful players I can't name, but rules are rules. I have to include Mississippi John Hurt and Doc Watson. The one thing that these to have in common is that as phenomenal as their playing is, it is always used in service to the song. Many great guitarists do the opposite, the song only being there to serve the "noodling".
When ranking guitarists I usually have separate lists for primarily acoustic players and predominately electric players as I consider them as different instruments. But the OP said only 3 in any style, so my list absolutely has to include Jimi.