WHOOOOO! Beat it! 4/20 beat my ass (maybe Foxy was apart of it), but man it was a good feeling to win! I did find out that you can do 1/9/8/7 before beating 4/20.
If want to know my strat for 4/20, and it can be used for Night 6. My strat was: Check both sides, then bring up the camera, only check Cam 1C (Booty Cave) and Cam 6 (Kitchen) back and forth, rise and repeat. When Freddy is at Cam 6, close the right door, then follow the strat. Yeah thats going to drain the power, and it'll take some tries; but it was the only thing I knew to do. So hopefully it'll help you conquer 4/20.