My drummer (who got this bass from his brother) gave me his mexican P-Bass for some repairworks. Once I removed the pickguard there was a round sticker near the fretboard and a routed hole which doesn't look amateurish and is also lacquered (see picture). There's no toogle-switch and none is needed since it's a single pickup bass. Besides, theres no routing to the electronic anyway. Sorry for the blurry picture of the Serial No. If necessary I'll post the Serial No. (don't have the bass with me at the moment). Could anyone help with some information on this?