Nilsson-Maxwell Windlass 3% or 10% V drop?

Hi:

Im replacing the two 35' cables to the windlass. Id like to size them
proper but not sure how much voltage drop is alowable.

I went to the Nilsson Website and they listed several North America
service centers. Ive called 6 of them and got message machines or the
tech isnt in now.

So here is my question.

Given a 30 year old Nilsson windlass how much voltage drop can the
Lucas motor handle: 3% or can I get a way with say 6-8% drop? Or will
it just grind away fine on 10% drop????

Also, what about new units? Id like to size the cables knowing that 30
year old pice of electrical equipment will need replacing somtime in
the future and dont want to under size the cables for any future
windlass. What voltage drop is alowable for new units?

I shouldnt be raising more than 500 lbs of gound tackle.
Suggestions?
Bob