Thanks for the tips. I went and borrowed a puller off a mate, worked a treat on one shaft, the other is still really tight. Gave it a bit more spray and left it for a while (don't have any penetrene but should go get some).
I checked the shaft lengths, they are the same luckily.
Never usually tip the motor over like that, only so I could get access. I have drained the oil out and am throwing that motor away anyway.
Hopefully I can get the other boss off. I had it done up pretty tight and it didn't move at all...
Thanks for the help.
Cheers
Sam