Border between header and sheet

I would like to place a border between my header and sheet. (both the page and the left hand column)
I tried adding a menu and making the text and the fill black thinking this would work as a border but it is too thick because I have 10 pages and it creates two lines. (It is really too thick with just one line but I could have lived with it.)

Is there a way to accomplish this.

I used Artisteer for most of the site, but it or me seems to have reached our limitations.

Thank you for your consideration.