By the way,
The little dark wood just in the middle between the pickup's is that where the wire's run?
I've made me a special tool to make such a channel.
I've bended an old screwdriver wich was made from normal steel (in other words: a cheap, very cheap, screwdriver) in an angle of 90 degrees. Grinded a kind of drill head on it and made the hole. It took one hour and a half but I think it was worth it.
You just push the head in, turn a little and pull it back out.
That way you can make a small hole.