I bought a used body for fairly cheap which I plan to make a bass out of. Anyway, to the point: the routing "holes" for pickup mounting are kind of soapbar-shaped, but rounded at the edges, about 4 1/2" by 1 1/2". Does anyone know what kind of pickup is supposed to go in here? If not... What if I were to mount a pickup that was a little smaller, like a J for instance? I was told to stick some foam in underneath and it'll sound fine. Has anyone ever done this - using the wrong size pickup without routing?