Nissan Z300 turbo 1986.

I took off the battery to start another car. When I reconnected the battery to the Z rear lights came on, no matter how many times I flick the light switch, the rear ed lights stay on. Perhaps a brake switch?

Unplug at Brake pedal switch, if light goes out, problem is at brake switch, adjusting may fix.
Have someone look at the rear lights and positively determine if it is Tail, or Brake lights. Have them press pedal, and turn on/off headlights