On the 360 engines, the exhaust will be one of the most important determining factors in jetting.
For short exhausts, that end around the foot pegs, you'll want to go +10 over stock (Strangely enough, you lose power, but still require more fuel. This exhaust length is not recommended).
If you're going two-into-one, +5 on the secondary main is a good place to start.
Longer exhausts will make the engine come alive right around the 7,000 RPM mark. I recommend a total exhaust length of between five and six feet, assuming you keep the stock diameters.
My 360 is bored out to 378cc, I'm running +1mm on the intake and exhaust valves, I've shaved the head for extra compression, I'm running a hot cam, AND I have open intakes with velocity stacks. Even with all that, I'm on +5 on the jetting (Running 115 secondary mains) and the bike is running well (at 200ft above sea level).
Short version: Keep your stock jetting, save your money, only buy jets once you've figured out if you need them.