I like Anderson type plugs for any high amperage accessory connection I make. This includes a 9k winch on my Jeep's winch bumper, power inverters off of a portable solar battery system, along with a 12k winch setup similar to yours on the tractor. I ran 14' of 0 gauge welding cable directly from the tractor battery back to the portable winch. Cabling and connector cost ~ $100. Plus I can also hookup the power inverters to the tractor with Anderson plugs, if necessary.
I also have a set of battery jumper cables I made with Anderson connectors I can use on the tractor also.