Drilling pipes
I drilled my pipes and removed the baffles and I love it. I'm waiting on my PCIII and will then will complete my mods with a SE aircleaner and go toppless.
This works on an R and I beleive a D as well, but not sure about the A models with curved pipes.
I used a 2 inch deep hole metal drill bit from Home Depot ($13), I used WD 40 to keep the drilling area lubricated. It only took a few minutes to drill out. You do not have to take the pipes off the bike to do this. The only slightly tricky part is starting the cut and keeping the drill from moving around. One the cut starts it becomes more steady. After cutting through back end I wiggled and pulled the baffles out.
I then used a dremmel to clean up my cut circle and give it a smooth edge. I imagine a file would work as well. I thn cleaned the metal files out with several wet paper towels and let dry.
After finishing I took a piece of cardboard and cut a round hole the size of the outter lip of the back of the pipes. I used this cardboard as a shield then I CAREFULLY spray painted the remaining inside lip of the pipes and holes with red high temperatire engine paint. (Auto zone $6) and let it dry. I used red as it looks SO COOL, (I'll post pictures later). I know it will darken with use but I can always clean it and paint it again.
That's it! No $500 pipes, no $150 mods. And there are several posts with maps that will work for this arrangement. With the money I saved I could even get a dyno and have a custom map make if I want.
Good Luck.