The regulator should be inside the left front cowl, somewhere behind the ABS symbol that is glued to the plastic there. It is oriented vertically in the drawing I have in my `06 500 Scarabeo GT service manual. I don't have the better version of Adobe Acrobat, so I cannot copy and paste the drawing to send it to you, but it is clearly marked as number 13 in the drawing. It appears to be about the size of a pocket camera.
I walked out to the patio and was going to uncover it and snap a photo for you, but it would require removing the center tunnel cover beside the battery cover and so forth, it is fairly involved.
Hopefully this info will help you find it.