1. If in 17 years, no other expert has said that the truck bomb was not sufficient to destroy the building, then I don't think you have to worry about "General Partin."
2. Jane Graham says she saw three men with drawings and some wire working in public during working hours. They could have been re-wiring the exit lights, for all we know.
a. If the investigators said, "Don't worry about them. We know who they were," then the conspiracy theorists would say the investigators were covering up for them.
b. If the investigators could and did name the men and their employer, then from that point on, the lives of those men would not be worth living. So they didn't name them.
c. But maybe all records of who was doing work around the place were destroyed, so who could tell?
Meanwhile, do you realize that by spreading these fears and suspicions, you are helping create the next Timothy McVeigh? -- somebody tough but not astute, angry but at the wrong people, and ready to be exploited.