Hi there,
You may find it helpful to retrieve a diagram of the 1991 Ford Taurus car door interior from websites such as the following:
1. Ford Taurus Forum- www.taurusclub.com
This website has a range of information, contacts, gallery and member benefits so that you could obtain a diagram by contacting the site which may be able to help you.
2. Ford Taurus.net - www.fordtaurus.net
This site holds a range of photos and diagrams for Ford Taurus first generation enthusiasts including 1991 images. You can get in contact with the site to get the visual diagrams you need to establish your require parts for the car.
3. Official Ford Parts Site- www.fordparts.com
You may find this site useful in obtaining the parts you need and they may be able to get a visual diagram of the 1991 Ford Taurus interior to meet your specific requirements.
4. Fax Auto Literature.com - http://www.faxonautoliterature.com/1991-Ford-Taurus-Mercury-Sable-Electrical-Troubleshooting-Manual-P12185.aspx
This website link contains the 1991 Ford Taurus Mercury Sable Electrical Troubleshooting Manual that you could purchase which may help you to obtain the information and diagrams you need.
I hope that these websites can help you to retrieve the information and visuals you need to see the location of parts for your Ford Taurus car.