Alright guys here it is...
I opened up my TCU images below:
http://www.flickr.com/photos/39434482@N05/3632099487/
http://www.flickr.com/photos/39434482@N05/3632099495/
http://www.flickr.com/photos/39434482@N05/3632099497/
I opebned all these little compartments on the wireless cpu unit and didn't find any GSM AT&T Sim chip...
Any thoughts??