Grimlock

Hello,
I have recently acquired a 89 JS550 in a trade. The machine's hull is in great condition, still has the factory bar code sticker on the rear. The engine however is a different story. Upon checking the engine i found both piston skirts were shattered and a small hole in crankcase. I do have a good complete bottom end from a '83 440. I work at a Kawasaki dealer and have crossed part numbers, i see the later 440's have the same part number as the 550 piston port motor, but the earlier part number's are different and do not supersede into the new numbers. I know working at a Kawi dealer i have access to alot of info, but this i can't seem to find an answer to. any help would be appreciated.