How do I get the Expieremental MIRV in Fallout 3?

Im building a collection to add to my house, so far I got everything from T-51b Power Armour to the Alien Blaster and more. All I want to complete it is teh Expieremental MIRV. I know you need the Keller Family Transcripts, I only found 1/5 on coincidence so far. Also I need the location name for where the MIRV is located. I have the Explorer perk so I already have the marker. Thanks.