While those T10 plugin LEDs are easy to fit I found 48 panel 5050 LEDs much better for your general overhead lights (assuming you have 2 single lights instead of the later double lights) here-
http://www.ebay.com.au/itm/Car-Interior-48-SMD-5050-LED-Light-Lamp-Panel-T10-Festoon-Dome-BA9S-DC-12V-White-/321289633832?pt=AU_Car_Parts_Accessories&hash=item4ace5ac028Forget the peel off stickon and remove it as it won't last and fix the panel on with dobs of silicon (4 corners and a couple to fix the fine wires so they can't vibrate away from the soldered connection at the back. The 24 panel ones are ideal for plugin bed lights if you have them.
As for the winch system it's well explained here-
http://www.hairfysh.com/index.php/our-travels/our-camper.htmland there are some posts with pics and videos around if you net search
As far as the Setec unit is concerned it is designed to run the 12V lights and any added 12V accessories while plugged into 240V as well as trickle charge any onboard battery when laid up. It is designed locally to handle quite variable 240V power supply such as you may find with diesel gennys, etc in remote areas.
PS: Here's a video which will give you an idea what those winch layout diagrams show-
Notice he says he was expecting a slave cable to break and that's because one had been chafing on the track pulley holder because in turn that compression spring guide is distorted and allowing it to happen. The guide should be replaced and fixed securely back in its right place.
Now bear in mind you can buy a slave cable set complete for $57 already swaged with adjuster eyebolts and nuts, etc so there's no need to chance your arm with handyman swaging and bulldog grips. Neither do you need heavier eyebolts as Jayco engineers know exactly what's needed. Yes if you should snap a cable it may overload the others but there's no excuse whatsoever for snapping a cable, as annual inspection would forewarn you if any were fraying and for whatever reason. Cable lifts are always designed with a Safe Working Load which is multiples below any cable's breaking strain, so you need a significant proportion of broken wires before a cable 'suddenly' breaks. Basically there aint no sudden about it.