Re: Apparently I'm not meant to have a boat...
OK life is not good just now but before you start up the chain saw lets inventory what you NEED to get things working again.
You need a damper plate, yup they break, you don't say what the engine and gearbox are but lets say its a Yanmar 2gm plate is about $160.
Most often you need to take the engine and gearbox out to work on it. It can be done afloat with a block and tackle off the boom but spread the load.
It has made it through 30 + years so it should be possible to put it back the way it was and get a few more. So think hard before making major and expensive changes.
REMEMBER IF IT AIN'T BROKE DON'T FIX IT.
If the engine mounts have seperated they DO need to be replaced. A failed mount may also have caused the misalignment.
4 mounts are going to be around $600.
So parts less than $1k sweat and knuckle blood come free if you do the job. Capn Fatty managed it so can you.