In order to have no scrapbook items when you start a Hardcore 100% run, you need to load a fresh file. "toggledebug" and then "unlockscenes" in the in-game console on the main menu. Then you play through "The Arrival" level until you get to the rundown house, then "load" in the console and it will bring you back to the main menu and you'll have hardcore unlocked.

NOTE: Information was created by Kain/MrWolfy. I'm just adding it here for everyone to have access to.

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