DRZ-400S jetting help

[mxboy96]

I've got a 2007 Suzuki DR-Z 400S. I did the 3x3 mod in top of the airbox with a K n' N air filter, completed with a Scorpion aftermarket exhaust. Big difference, let me tell ya. It's still got the stock crappy vacuum carb, but it'll have to work for now. The stock jetting is a 142.5 main, 22.5 slow, and 4th clip on the needle. I put a dynojet jet kit in it, but that was for an aftermarket exhaust with stock airbox. And I've been told that they came lean from the factory anyway because of emissions crap. The plug is almost a grayish on the tip, but black around the sides and bottom of the insulator. My buddy's got a 400Z quad with the exact same setup, and he runs a 160 main. Basically, I would like to know what jetting setup is just right for my bike considering the airbox mod and aftermarket exhaust. I just want it to be dead on like it should so it's not too lean to damage anything and not to rich just plain cause it shouldn't be. My elevation is right at 2500ft above sea level. Any opinions and all help are/is welcome!! Thanks!!