Sandi,
If you cannot find a way to do what you want in your printer setup, you can add a watermark in a PDF. Print your document to the Adobe PDF printer to create the PDF. Then open the PDF in Acrobat and add the watermark by selecting Document > Watermark > Add. In the dialog box, you can specify the text of the water mark, its font, its size, its color, its position, etc. Do not choose a gray color, instead choose black or some other solid color; then set the transparency to whatever percentage you want. This will allow text underneath the watermark to show through. You can also specify on which pages the water mark appears. You can also do multiple watermarks.
I have Acrobat Professional, so I do not know whether this feature is available in Acrobat Standard or even Acrobat Reader.
If you do not have this feature in your version of Acrobat, you can add the watermark to your master pages in FrameMaker, but then you have to remove them when you do not want them to display.
Van