So, I wanted to make a small mod to set some caravan merchants and som BOS characters essential, because I don't want them to die while they roam. The problem is, some of them are both in the vanilla game and in the DLCs. My question is: to mod them, should I load the Fallout esm or the Broken Steel esm in the GECK? If I load the Fallout esm and mod something that appears also in a DLC, will the mod work or will the DLC overwrite it?