I asked about this at wikisource:Wikisource:Scriptorium#Possible topical WikiProjects? and got the "we do things differently here" responses visible there, which seem to indicate that the less-successful "single work" WikiProject model that has been used to date seems maybe less than likely to change anytime soon. I could however get together a list of the extant indexes which do exist there which could maybe be added to the wikisource:Portal:Military history and its extant offshoots and could try to get together lists of pages in Encyclopedia Britannica and other general reference sources that already exist there, which maybe could be put on a page there or here.