As I posted in another thread, I recently pulled my K321 apart for a rebuild. I have NDH 3308 crank bearings in it. The OP had been told by another member the original bearings crossed over to 6308. I have a new pair of SKS 7308 bearings on hand. Are these acceptable to use on the crankshaft? The only difference I have seen between the two are the 7308 have a higher load rating, but are rated at 9000rpm, while the 6308 are rated at 10,000rpm. Any help on this would be greatly appreciated.