How do i mod this type of pipe baffle?.

10x fetor. i really appriciate your help. just another last question. i was reading in other sections especially in '2 stroke muffler question' that by cutting out the baffle will run the engine more lean. i am currently running o the 3rd slot that is nearly all rich mixture, isn't that enough or i have to go to the extreme and put the circlip on the richest position?
It's VERY doubtful that u will need to go to a richer mixture cos these exhaust mods only lean the mixture out SLIGHTLY.