[JAXSONJONES]

Hey guys,
Got a new question. My truck is a 4000, and the cab is painted with bed liner. I found a pretty nice vin# 3505 I’m assuming is a 3500. The biggest difference I can see is my fender flares are much bigger. This 3500’s flares are big, bigger than a normal pickup, but not nearly as big as 4000’s. My question is are the cabs interchangeable? Or what are the differences?
Thanks
Mike