It gives me all kinds of horrors looking at some of the previous posts, I've taught winch use & safety to both military & civilian also used tirfors & brano pulling machines for years take it from me they are hard work, effective yes but for a lwb paj or LR110 you will need a 3ton rating or you'll need to keep a stock of shear pins.
As for running a Hyd winch from the power steering pump, simple..dont.! it will be slow & it is not rated for it, the steering pump will fail then try driving home after your unstuck.
Will you actually need a winch? if its front mounted sods law you will need to get out backwards, I've not used mine for self recovery ever, used it to lift an engine & pull a dead horse from a stable though
a demountable is the best of both worlds - can be mounted in the front or rear or left at home.!
As for fitting a 2nd battery the winch should be powered from the main battery to avoid voltage drops associated with the split charge.
be safe.
90.