I need to route a channel, on the face of the guitar body, about 1/8" wide by about 7/16" deep & it needs to follow the shape of the guitar @ 9/16" on center. Is there a guide that I can use? or something I could construct myself, so that I can follow the shapes (inward/outward curves on a Tele)? Most guides (that I've seen) have a rail that would cause you to lose your distance from the edge on outward curves. Any ideas? Thanks!