ServerActors=NPLoader_v16b.NPLActor is the line that does the automatic install of ace on server boot. To completely remove ACE all together you need to remove the following lines:
ServerPackages=NPLoader_v16b
ServerPackages=NPLoaderLLU_v16b
ServerPackages=NPLoaderLLD_v16b
ServerPackages=NPLoaderLLS_v16b
ServerPackages=ACEv08h_Cdll
ServerPackages=IACEv08c
ServerPackages=ACEv08h_C
ServerActors=NPLoader_v16b.NPLActor
ServerActors=ACEv08h_S.ACEActor
ServerActors=ACEv08h_EH.ACEEventActor
Then you will need to delete the following files from the system folder: