99 kx 250 set up for woods HS & 6th gear??

I am setting up a 99 kx250 for woods riding and Hare Scrambles.
I plan on installing a flywheelweight and steel clutch plates and an o-ring chain. Does anybody have any other suggestions and possible sprocket set ups. Also does anybody know if they make a 6th gear to add??
Thanks for any info