On the Gauntlet Blog I look at my process for creating my recent twelve session Delta Green series using The Fall of Delta Green: foes, themes, etc and present my rough scenario sketch for the first mission the team handled.
You can find that here: https://www.gauntlet-rpg.com/blog/delta-green-divergence-campaign-concept-scenario
The Keeper for the game: https://docs.google.com/spreadsheets/d/1Vg6vi3_5q8VeqRSHswhwbifzrRe0dDvjZ5xZQui8bXk/edit#gid=502885382
AP Playlist: https://www.youtube.com/playlist?list=PLUKV1MEOXoTWDGqoZxv7tK5X69lYwdert