It's unlikely that the seats are directly interchangeable without modification. While both are Dodge Ram trucks, the 2002 1500 and the 2004 3500 are different generations and have different chassis and interior designs. The seat mounting points, seat tracks, and even the electrical connectors are likely different.
You might find *some* similarities, but you'd almost certainly need to adapt the mounting brackets or even fabricate new ones to get them to fit. It's a much more involved project than a simple swap.
