Synthetic rope is great and something to eventually install if you use your winch much but try this first...
Unspool your wire rope so only 2-3 wraps are left on the drum. Connect its hook up to something solid that won't move... like to another Jeep's tow hook. Back your Jeep up so the wire rope is taut. Then pull your parking brake lever up so it's fairly tight... at least several clicks-worth. Then after putting gloves on, use the remote to cause the winch to pull your Jeep forward against the parking brake while guiding the wire rope onto the drum with your other hand. Remember to shift the transfer case or transmission into neutral first of course. The parking brake should be tight enough so it's placing at least 250 lbs. or so of resistance against the winch so the wire rope will be tight like it came from the factory.
That is how I rewound my wire ropes and how I continued to rewind my synthetic ropes... the key is having enough resistance for the winch to pull against so the rope is good and tight. So tight that winching won't cause the rope to be pulled down through the layers which can damage it.
For what its worth, I just did this to my Jeep over the weekend. I unspooled the cable and stood on the line as it rewound. I guided safely with my hands as needed. End results were very good. Once the hook got to my feet, I just put body weight against it for the last couple wraps to keep it tight.
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