Where is the reverse light switch on c6 trans 1973 mustang?

On a 1973 Mustang with a C6 transmission, the reverse light switch is typically located on the transmission itself. It is mounted on the driver's side of the transmission case. When the transmission is shifted into reverse, the switch is activated, turning on the reverse lights. If you're having trouble locating it, consulting the vehicle's service manual can provide more specific guidance.