If you don't feel like being a Minuteman this playthrough, this simple mod will successfully set Jun, Marcy, Sturges, and Mama Murphey to non-essential. It does not, at the moment, appear to be working for Preston (any help would be lovely!), but I've included a bat file that you can use to get rid of his essential state too. Just open the console with the ` key and type "bat nogarvey" without quotes and hit enter. Now you can kill them all.


Keep in mind that this *does* disable the radiant quests that send you around to all the different settlements, but as soon as I find a way to supplant that with F04Edit or the GECK eventually I'll make sure to do that. It may also make it impossible to recruit Codsworth if you don't finish their first quest before killing them.
 
I added a version of each that also gives the Minutemen the 'protected' status, meaning only you can kill them. EDIT: Unfortunately this does not seem to work. With this version the Minutemen don't die for some reason. Pulling it.

Preston still isn't dying properly. I recommend that when you want to kill him you target him in the command console, type "toggleai", kill him, and toggle his AI again. This worked for me. He seems to stay dead and in the Museum of Freedom.

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