http://www.tugnuts.com/viewtopic.php?f=5&t=4000&p=29464&hilit=honda+generator#p29464
At the above link that takes you to another recent thread on this forum, Osprey explains in detail about the reverse polarity lite coming on when a Honda generator is used on a Ranger Tug, including why it comes on and how to resolve it if the reverse polarity light bugs you.
Wolf Pack has used a Honda 2000i on the hook with great success. YES, the reverse polarity light comes on. YES, the generator charges the batteries just fine.
Wolf Pack uses one of these
http://www.defender.com/product3.jsp?path=-1|328|2290035|2290037&id=1352456 to plug into the generator along with one of these
http://www.amazon.com/dp/B001GICVAM...e=asn&creative=395105&creativeASIN=B001GICVAM to go to the boat's shorepower inlet. Note that I did modify the female end of the 12 ft Conntek cable with a SmartPlug connector to plug into the boat's shorepower inlet (which, incidentally, is also a SmartPlug inlet). Typcally, we either set the generator on the dock finger (ie; like at Dockton County Park marina or Coupeville, WA marina, neither of which have shore power) or on the swim platform when at anchor. When at anchor we use a suitably sized storage tub from Walmart with about 7" high sides and holes drilled in the bottom to keep the generator mostly dry (an idea that was posted in this forum by knotflying some time back) and a few strong quality bungees to make sure it stays on the platform. When underway, we move the generator into the cockpit under the BBQ which is out of the way of crew traffic (idea also from knotflying). Our Honda gets near to 12 - 14 hours on a tank of gas with the generator's ECO switch on if I can keep the Admiral away from the microwave and if I can also keep her electric fying pan hidden--out of sight out of mind <smile>.
Of course you should all remember to make sure shore power is turned on at your boat's control panel when the generator is running <smile, experience speaking, smile>.
We also use the same generator when camping in our camper with great success there as well. Camper control panel doesn't have the pesky reverse polarity indicator, so no issue there.
The reverse polarity light on Wolf Pack does not "bug" Wolf Pack, so we won't be modifying our trusty Honda any time soon.
Hope this info helps.
Gene R
Wolf Pack