so the mods that are in my inventory in the Pip-Boy under "Mods"

they are actually the ones that I don't have on my weapons right now?

if I move them to a box, I'll still keep all my weapons modded as they were?

my inventory is currently flooded with those Mods (40+) and I'd love to move them out of my inventory

Yes the mods in your inventory is the mods you replaced when you moded your gun, so you can sell them without losing the mods thats actually on your weapons and armour.

As Remmus said. However, you might want to hold on to some mods (e.g. .308 chambered receiver in case you find it hard to locate .50 rounds). If you sell the mods, you have to have the necessary components to build a new one, if you need to swap back. When you already have the mod in your inventory, it can be attached without cost.

alright thanks

yeah, I just planned to store them in a safe near my workbench then ^^

Keep them in the workbench invetory and you will use them on other weapons i think

More than that. If you want to strip off a good component from one gun to use on another, you have to make the something to replace it with (except for muzzle attachments).

So it's a good idea to keep the standard or lesser versions. Think of it as a middle man for changing mods around.