End Boss Plasma Gun
horriganwf
The forum you posted on was for the game world and setting discussions; A gameplay question ought to have been posted in the Gameplay forum.
Alas, you need to have a character killed (An Enclave Trooper or an NPC; I like to use Myron for this purpose) on the hex Frank was standing on. Then, try to loot it, and use the arrows to switch to looting Frank's corpse. Then you can steal his weapons.
It is possible that you'll need to lower the violence setting in options and not have Bloody Mess, I read somewhere.