Look at the tail gate cables on different trucks most of them are 1/4" cable, make sure you don't figure in the plastic cover as part of the 1/4". The ends are silver braised into the cable for a strong connection, and they are the perfect lenght for this application.
Note what truck and year, then get them from a parts store, I don't advocate stealing them from the truck. The mayor of East Wendover makes a killing on these every year along with metal tire valve caps, and inertial shut of switches at his parts store.
Don't use the cables from a Nissan truck they could be damaged from landing airliners, snowboarding of mountain tops, and pulling C vans up out of the canyon. Oh and pushing dune buggies over dunes from a dead stop.
Steve