Saving Old Seagulls

Finding that a pig of a job is always separation of the drive shaft from the pinion and crankshaft (but particularly the pinion due to corrosion), I wondered if replacement with a stainless item might be a good idea.

Has anybody ever done this?

Once its apart to fit a stainless shaft, you don't need to, as it usually takes years to get into that condition, plus you can stop it happening again once its apart.
I do have a Stainless exhaust on one motor though.

Adding stainless to a steel part will only make the steel rust faster! I would not do it!