Saving Old Seagulls

Recently I had an issue with a stuck gearbox screw. WD40. Penetrating Oil. ATF & acetone. Correct size screwdriver bought specially for the purpose and much straining and I have to say some swearing. Wouldn't budge. Looked around for an engineering firm near me. Nothing. But I did find a seller ...

Tef-Gel looks like a good compound except it seems to be intended for anything which doesn't get hot - at least there is no specific statement by the manufacturer that it is intended for use with engines. The yanks are keen on something called 'Jet-Lube Anti-Sieze Marine Grade' which has a stated up...

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?

Because I suspect the oil seals may be leaking...
Because they are covered in something unpleasant and I'd like to clean them...
Because I would like to know that my seagull is 100% servicable...

Hi all I'm having a spot of bother with a 3hp sealed gearbox reclaimed from a scrapper. All was going well, got all the screws to release, top flange off ok, prop shaft removed, no play in any of the bronze bushes etc. I had sort of expected that the brass (bronze?) components which make up the end ...