So I decided to take the pickguard off my MIM Fender Fretless Jazz bass to see if the rout for the neck pickup was good like the bridge pickup rout or just plain sloppy. Upon taking off the pickguard I noticed a hole probably 1.5 cm in diameter and 1 cm in depth going into body. Any clue what this is there for and do others with MIM jazzes have this? See attached pictures. Thanks.