Yes, light switches. The 4L80E has four solenoids, two for shifting, one for torque converter lockup and one for line pressure. Mann couldn't control the line pressure without the computer, so the transmission always runs at maximum line pressure which causes slightly harsher shifts. He installed one switch on the dash to control the torque converter, and two more - one of them black - for shifting. The speedometer? The transmission has an electric speedo output, so Mann picked up an Android off Craigslist and he uses an app for the display.
When he puts the floor shifter in drive, he flips the light switches to change gears. Or he can set the switches and change gears with the floor shifter. It's kooky to read about - and kinda kooky to watch, frankly - but it's neat and it works. Check it out in the video below.