First off, grab my FixSwap and Removers mods and drop them in your Mod Folder
Load your “Never Fade Away” save file before entering the room, and open AMM
Spawn > At Own Risk > Johnny mirror
The spawned Johnny will be invisible, you’ll need to scan his feet shadow to be able to swap!
Make a quick save and reload it
Make sure to despawn your V/Johnny before entering the room!
There will be small a moment, when Alt takes off Johnny’s glasses, where your V will turn invisible ; That’s ok, they’ll pop right back when the mirror scene start!