In addition to all the suggestions above, try finding some tinned silicone wire as the coating is much softer and flexible which is especially good for bending in small spaces and for passing through those couplings that connect the tender to the engine where most of the wire damage occurs. Also remember to have a little slack in the wire for coupler movement.
https://www.ebay.com/sch/i.html?_from=R4...e&_sacat=0
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