Yamaha 85aet 688

Hi,
Ive got a yamaha 85aet 688 serial no:406769. Does anyone know what year it is? it is a european engine. Also does a powerhead off a origin model fit onto the casing?

[jb123]

688 1978- 85AE

best thing to do about powerheads is compare base gaskets.

Thanks jb123, im still trying to decide what to do as i live in ireland and will have to get the powerhead from the UK or USA.