Was the clutch pack getting replaced due to wear? Or an upgrade?
I had a 550 SECA that I thought the clutch was worn; slippage. Put the Barnett kit in, and took a look at the OE. As it turned out, my issue was just weak springs; clutch plates were fine. I thought my FJ's clutch was acting up, again with slippage. Before wasting money on a clutch kit, I took the old clutch pack & the weird circle spring to a tech I trusted. First thing he did was remove a very thin wire from between some of the clutch plates and throw it away. Apparently, Yamaha puts that wire in there as a wear indicator. As your fiber wears, the wire prevents full "clamp", and allows slippage. As it turned, the clutch pack was still good, and my back tires was breaking loose at about 6,100 rpm.
My point is, if you're replacing for "wear", it may not be worn out.