This number should appear on the "modification label" after a reflash is done:

[ CALIFORNIA NUMBERS ARE DIFFERENT! THESE ARE FED NUMBERS. ]

3500 auto - #55351105 AT

3500 man - #55351100 AT

2500 auto - #55350105 AT

2500 man - #55350100 AT

No distinction is given for cab/chassis models

Source info(previously posted under different subject heading) is here:

http://www.turbodieselregister.com/f...b-listing.html