So what's the best way to fit 325/60/18 on the nbs or should I stick with 285/65/18. I just like the look of the bigger tire a little better.

Dutchie what wheels are you running now? Don't know about a 2500 but a friend just installed Toyo MT's 33X12.5X18 on an 08 1500 and they look good. His mods were a 2 inch leveling on the front and banging in the rear fender. BTW he has the original wheels on.

Actually the front fender just the back part under the plastic.

Sorry should have included that I'm looking at a few different 18" rims with +18 to +30 offset, XD Hoss or Moto Metal 956 leaning toward a 285/65/18 but like the look of the 325/60. Running stock wheels now with 285/75/16 and a little crank on the t-bars.