I can post where the actuators are on a 2000 Bonneville, but that likely isn't going to help you much for the Buick. To get that information, there are probably a few options...some better than other. You could get a FSM or Chiltons for that vehicle. You could purchase a subscription to AlldataDiy. As it'* the neighbor'* car, you're not likely to like those options.
Might be something for the neighbor to consider.
The other options are to see what the public library may have for service manuals, and finally - just getting in there and seeing what you find.
Black 2000 SSEi, Silverstar Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, drilled 180 degree thermostat, Intense FWI, PCM, shift kit, and 3.4 Pulley. Solid front mount.