After reading some great treads from WSTAR on
wstar's Journal also RCZ and others on the topic of installing the "STILLEN light weight crank pulley" and underdrive pulley, I was able to get the info I was looking for. If you plan on doing this mod and have questions about the "balancer" issues, you will be very well informed. WSTAR has a good write up in his journal discussing the installation issues and how his butt dyno results turned out.