I am a Graphic Designer by profession, and was going over some ideas for you when I read the post above, about having a young person involved. I think this is a fantastic idea. When I was younger, I got into design by illustrating skateboard deck art for friends. So, maybe some pointers or...
Did you ever figure out what it was? I'm asking because I have a new 21' JLU Willys and noticed the sound coming from behind the glove box, while the Jeep was off.