You can keep them in your inventory, that's irrelevant, mate. Just do what you have to do. After the moment you move the frozen stack around you lose the address, so do everything you must before that.
Here's a video on another way how to abuse freeze dupe, this time on crafting.
- your frozen stack must have at least twice the amount of items necessary to craft one equip.
- if the required stack is over 10, have a safety stack below your frozen stack (i.e. If it asks for 12 iron)
- does not work with items requiring 20 parts like SWAT top and bottom, you need to have your frozen stack at the bottom of your inventory and splitting what you need without consuming that stack.
This is just a shortcut to the same thing, but faster. I'm trying to get a second weapon crate to confirm if they stack or not. If they do, we have an infinite source of armor and weapons easily.