+1 gggGary, while it cured slipping at higher rpm's the best treat ( 4 me) is the lack of "snatch" at take off. I am not an educated man but my best guess is the extra plate offered some xtra damping on take off helping the little springs on the back absorb the shock? Somewhat like Yamaha did with the extra plate.
I got busy with other things and stopped riding that bike several years ago. If I had to do it again I would have sourced an earlier clutch and not done the machining to a later clutch. I think on a dollar 4 dollar basis it would be cheaper. But I don't own a lathe. . . .