FOIAs and the Angolans
Jo, sorry for the late reply. Didn't know it was here.
The FBI documents were interesting but about the only thing they revealed is that the FBI didn't know aviation and that there was a turf battle between them and the State Dept. They looked for the airplane with enthusiasm only for a few months. Then the search pretty much faded out. Based on what I have read, I found a few things they missed.