If you don't want to burn it down, I would stick with a single pipe. That 500 is an extremely impressive power plant as it is. I bought a 98 new and looked into the same stuff. Suzuki did a real good job with the design of that mill, getting more out of that than the 600.
I was told by several different shops this: If you port and pipe it, it will become very fragile. Once I heard that the third time frmo a reputeable shop, I looked into other mods (made it lighter).
If you want more power, upgrade to a 600 and mod that. There are more aftermarket parts out there and they are not quite as high strung to start with.
04 King Cat Mountain Mod - Black - Lightweight - **ORANGE PARTS ARE FOR SALE**
97 ZRT 600 - Magic Triples - Reeds - AGLT - Soon to get a 700 kit
80 Trailcat 3000 - Very nice original
76 440Z Mod - Drag sled
74 295 El Tigre - Stock Oval sled
72 440 Cheetah - Stock
72 292 Puma Mod - 71 King hood/pan - Early small tank and Lynx seat - T4B292 w/ reed, TM38 and custom pipe- Way cool toy!
If you need dyno testing, custom porting or pipes made, contact me as I do this to support my addiction!