Aftermarket parts give the following specs:
1. 22321-MT3-000 @9 - 139mm x 2.0 mm Clutch Steel Plate with 28 Pegs
2. 22201-MA7-000 @2 - 151mm x 3.5mm Clutch Friction Plate with 12 Pegs
3. 22201-MY3-000 @8 - 150mm x 3.8mm Clutch Friction Plate with 12 Pegs
The clutch pack therefore is 55.4mm which is well within range and within 0.32mm of maximum. A new clutch pack soaked in oil is probabley close to maximum. When I measure my 120,000 km old oem steel pack (only) I get 18mm, within 0.02mm, so virtually no wear. Sure they still a little greasy with oil but I can say changing the steel plates if they are straight is a waste of time.
If some body measures a new plate and gets 2.03mm (.27mm difference in total) then it might be worthwhile.
Regards
Garry