I'm going to assume you are younger than I am and were in the Air Force, specifically the maintenance field more recently than I. I was an engine mechanic in 1982 and retrained into ATC in 1992. By "signing off" things, do you mean red X's, diagonals, and dashes, in other words, signing off things that would otherwise ground the aircraft? Was your sign off more of a shop checklist kind of thing? In my experience, 7 levels and above were the only ones authorized to sign off things to make the aircraft airworthy again.
By the way, I never failed to unhook a cannon plug prior to removing an engine. So....it wasn't me.