I found a great diy step-by-step online showing how to disable DRLs.
Here:
Disabling Daily Runing Lights (DRL's) - How-To - NewBeetle.org Forums
I have but one critique. And, that is that the pictures of the connection are a bit misleading (or at least they were to me).
In an attempt to make it clearer which connection is to be disrupted, I have taken what I feel to be a better picture.
Good for around a 1.5% mpg improvement!!!
good luck