Phantom Turning Tail Lights On my MR-2

My car is a 1986 Toyota MR-2. In cooler weather gremlins turn my tail lights on and run my battery down. I just replaced an 8-year battery that I only had for 4-5 years. Two days later it happened again. If I hit the brake pedal a couple of times and pull it up with the top of my shoe, it will turn the lights out. Any idea what’s causing this?