I have a 99 YZ400F that currently has a white bros e2000 pipe on it. Unfortunately it's way too loud, so I'm going back to a stick pipe. However, I also need a spark arrestor so I bought a WR400 muffler for it. I'm confident it will fit okay, and I know there will be some power loss (actually I'd prefer the power delivery to be less "snappy" anyway). I understand that I'll need to re-jet. I'm about 1000' above sea level, and was wondering what the best (cheapest) way to find the correct jet was. Right now I'm thinking about taking it to my dealer, but that's going to be expensive.