aftermarket leather

Hi,
I bought an 06 Maxima and I took the car to get the window's tinted. The owner of the tint shop also does upholstery. He told me that my leather interior is aftermarket and not factory installed. I took it to the dealer and they told me that It was factory installed leather.

How would I be able to get a definitive answer if my interior is factory installed or aftermarket?. Is their a place to check on the the seats?, and if it is aftermarket is it legal for a dealer to do this?.

Thanks
Wood12345

Does your interior look like this,

http://www.nissanhelp.com/Models/2006/Maxima/5maxima_gal_big06.jpg

http://www.nissanhelp.com/Models/2006/Maxima/5maxima_gal_big09.jpg

http://www.nissanhelp.com/Models/2004/Maxima/05_2005_maxima_sl.jpg

If so then it is factory installed.