(boxer trim) 2tone colors on 308's

Guys! Just wanted to know if on the 308's that came from the factory with 2 tone paint had two paint codes listed on the car somewhere? If not,how would you know if in fact it actually came that way if you were say the third or forth owner? Could FNA or the factory confirm this without to much hassle? Just throwing the question out there. I must admit I think they look great, and sometimes consider doing it to my red 84 GTB for about a minute and then come to my senses.Have any of you done this?