Todd,
The lead from the cowl lamps themselves goes down along the left edge of the firewall insulator (tucked into the gap between the left edge and vertical cowl sheet metal) and down the left side of the #1 floor board to the outside of the left leg of the firewall. The lead passes through a rubber grommet in the hole in roughly the center of the firewall leg and from there down to connect to the lead from the light switch.