Willy
That's a PowerWinch. With the exception of the Laminison-Dutton Winch it's probably the best boat winch on the market. Can't tell from the pics what model he has, (It looks like a 712 judging from the red stripe) but they all use the same connector though. It's a "Plastic Winch Plug Model #P7810500AJ". You can buy them on eBay or through most marina shops or directly from Power Winch.
If you're going to go the electric winch route I'd say that for our V20's the PowerWinch 712 or the Model 4000 is perfect. (I use a 4000) Given that the 712 is rated for up to a max boat weight of 7500 lbs I'd guess that' it's more than sufficient for Fishbones. The Powerwinch uses a lanyard that connects to a switch next to the clutch wheel on the winch itself, so you can stand in the water at the trailer and by simply pulling on the lanyard you can activate the winch and pull the boat onto the trailer while you guide it.
Unless you're going to run it from a battery on the trailer you have to run your wire as a dedicated line right from your vehicle battery to the winch. Your 7 pin connector wires are not heavy enough to stand up to the amperage draw that the winch makes (from the factory it uses a 60 amp circuit breaker). ALso you need (should) install a circuit breaker from the positive terminal on your battery and then connect the wire to that breaker. (Truthfully I've been using mine without a breaker since I installed it several years and several boats ago without any problems).
What I did with mine was to run the heavy wire from the battery under my Jeep along the frame and then up to and inside my Jeep. Then I installed a set of Anderson Power Products 50A connectors to that wire and a ground wire and another set from the wire to my winch wire.
The positive wire comes from the battery and the negative wire just goes to the frame of the vehicle. That way the wires are always in the vehicle and out of harms way until I need it, and then it's just a simple task to plug the two Anderson connectors together and plug in the winch on the other side.
Hope this helps... If you have any questions I'll be happy to try and answer them for you.
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1987 V20 w/1987 150HP Yamaha on a Shoreland'r Trailer
1978 16.5 Airslot w/1996 120HP Force on a Four Winns trailer
1996 V21 w/1993 200HP Mercury on a Shoreline Trailer
All towed by a 5.7L Hemi Durango.
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