taillight harness on 1950 F1-Help

[oneoldtruckguy]

Got a new harness to wire my taillights on a 1950 F1 Pickup. I already put the complete harness on the engine to dash. I have power on the green wire coming from light switch to the taillight at the firewall. Then I have power to the brake light switch but NO Power at the rear harness where it plugs into the taillights. What am I doing wrong???? Otherwise Power at the front of the harness but no power at the rear.