If you decide to do this, it is expected that you already know how to use MpClothes

In order to duplicate the items so you do not replace any original EUP files:
1. Take the item's ydd and corresponding ytd files
2. Drag them to your desktop
3. Place them in the appropriate MPclothes DLC
4. Rename them accordingly

Now you can place the textures into the ytd files

You'll then have to find the appropriate number in the EUP menu (they will usually be within the last 100-150 numbers for components and the last few numbers for hats)