I'll also be interested to see the replies to this Jewgaffer-I'm in a similar situation,I have a 115hp Merc 2 stroke with i/2 a tank of year old fuel due to illness that turned out to be bowel cancer,since removed, and despite mop-up chemo I'm feeling the enthusiasm returning, but have the same concerns about running the old fuel.It's terrific to see you posting again,I hope you're up and about as soon as possible.
Cheers,
Dave.