Engine Serial Number Decoding

[ManChild]

Does anybody know how to tell an engines model year based on the serial number? I put a new engine in my bike and was going to swap my clutch into the new one, but the clutch basket is completly different. I was told the engine was a '96 but it was in a '93 frame when I bought it and I want to be sure what I've got before I go and order parts for it.
Engine serial #-N705-166

[squiggy]

Post pics of the clutch basket and/or "bolt plate". It's not called a bolt plate but it's the clutch plate that's held on at the begining of the clutch with the bolts.

[ManChild]

old clutch 003.jpg

old clutch 002.jpgI have already put the new engine back together so no pics, but here are pics of my old one and I can explain the differance. The old bolt plate is 4 bolt the new one is 6. If you look around the edge of the basket, the old one has large gaps for the clutch disks to slide in, the new one is solid around the outside with much smaller teeth. The new clutch disks have teeth more like a gear around out side.
Thanks for the help.
---give me a minute on the pics, gotta figure out how to convert them to something with a web address, okay think i figured out the attatchments.

[arsenic]

what year is the old clutch out of?

[ManChild]

the old clutch is out of a 1991