The truck I am picking up next week, was built in 11/03, and the dealer invoice sais NAA Federal emissions. Do I have the 305/555 or the 325/600?

I'm hoping its the 305/555 which is not supposed to have a cat converter. How can I know before I pick up the vehicle?

 

Built in 11/03, its going to be the 305/555. You could tell by looking at the dealer invoice for how much the Cummins engine option cost. If it's $5360, it's the 325/600. The 305/555 is a little bit less. Congrats on the truck by the way.

 

There is a sticker on the side of the "vanity" cover (on top of valve cover) that tells you what the horsepower is at the rated speed (2900rpm for both).