Managed to remove the four bolts holding down the engine this afternoon and disconnect what appeared to be an old starter motor. I scratched around to see how to disconnect the shaft – looks like I will have to cut this off – the bolts holding the universal joint in place are solid rust – with think about it some more first though.
Will try to take some pictures and add to this post later.
After mowing the lawns and cleaning out the garage I had some free time so jumped on ANZAC and started to disconnect the motor and fuel tank. I removed the batteries, battery stand, bulge pumps, disconnected the fuel lines, removed the redundant wiring, and pulled out the exhaust (full of water).
The last of the wheelhouse floor came out easily, but disconnecting the shaft looks as though it may take some persuasion from the angle grinder.
I located the motor hold down bolts and managed to loosen two of the four, the last two are in difficult to reach locations, but will have a better go at these later this week.