i just bought a gibson es-135 a couple days ago and i love so very much. im gonna be stickin with this archtop for a while now. i bought it with p-90s and now have lots of problems with feedback in this guitar. not on clean but with distortion i get this screachy noise and it really bugs me. can you guys suggest some tricks or tips to eliminate feedback problems. and also. how the hell do i change these pickups.