[Putershark]

Definitely need a good combination of both force and finesse to break it free without breaking something else in the process

I say the Blue Wrench (torch) would come in handy right about now, but just barley heat up the shaft and then let it cool back down and see if that helps. And BE CAREFUL not to torch up the whole boat in the process

And the application of a rubber mallet for a little impact shock may also come in handy on the end of shaft to help break free the rust. I do not though recommend trying to break it free by using the helm, and just "wiggle" the engine back and forth till it breaks free