First winch easy, second.... Help!

[Wife of Lofticus]

Successfully serviced first winch yesterday, Lewmar 40st, started second today. Another Lewmar 40st but it was converted to an electric winch prior to our ownership.
Stripped the winch, going well, until I got to the final task of removing the smaller gear assembly. This time the assembly would not slide out. It is not stuck to the bottom as I can move it up slightly, but it appears to be pinned through the middle to the underneath electric unit.
I have accessed the electrical unit from within the boat but can see no obvious way of releasing this gear assembly.
What am I missing?

 

[SHUG]

What seems to be missing is replies!
The assembly procedure is given here:http://www.lewmar.com/%5Cassets%5Cimg%5Cdataset%5CManual-Elec_win_WEB.pdf
It looks like the gearbox is attached to the winch by screws which may only be accessible from below deck.