Create a chapter with different style, using Tufte book

I'm finishing a book using Tufte-Style Book (b5paper,twoside,justified). I just arrived at the last chapter (10th) and want it to be different from the previous 9, as it contains different information to be rapidly consulted when needed. As such, I would like to have (only on this chapter), for instance, a vertical color bar at the outer margins (making it readily visible for someone picking up the book) or a horizontal bar at the top of the page. This is probably trivial to some of you, but I'm struggling to find a solution. I'm approaching the deadline and I'm stuck in the very last chapter. Any help would be tremendously welcome to a newbie as myself.

Edit:

I managed to create the vertical bars for the last "special" chapter, using a new pagestyle (see below). However, a new problem arisen as the vertical bars continue to the index. It seems that the AddEverypageHook cannot be de-activated. Any suggestions?

\fancypagestyle{special_chapter}{

\ifthenelse{\isodd{\thepage}}%
{\backgroundsetup{angle=0,position={0.1\textwidth,-
.7\textheight},%
contents={\tikz[remember picture,overlay]{ %
\coordinate (x) at (current page marginpar area.south west|-current page.south west);
\draw[draw=none,fill=gray!20](x)rectangle(current page.north east);}}}}%
{\backgroundsetup{angle=0,position={-0.32\textwidth,-
.7\textheight},%
contents={\tikz[remember picture,overlay]{ %
\coordinate (x) at (current page marginpar area.south west|-current page.south west);
\draw[draw=none,fill=gray!20](x)rectangle(current page.north west);}}}}%
\BgMaterial}
\AtEndDocument{\thispagestyle{plain}}
}


I managed to create the vertical bars for the last "special" chapter, using a new pagestyle (see below). However, a new problem arisen as the vertical bars continue to the index. It seems that the AddEverypageHook cannot be de-activated. Any suggestions?

Thanks,

Nuno

\fancypagestyle{special_chapter}{

\ifthenelse{\isodd{\thepage}}%
{\backgroundsetup{angle=0,position={0.1\textwidth,-
.7\textheight},%
contents={\tikz[remember picture,overlay]{ %
\coordinate (x) at (current page marginpar area.south west|-current page.south west);
\draw[draw=none,fill=gray!20](x)rectangle(current page.north east);}}}}%
{\backgroundsetup{angle=0,position={-0.32\textwidth,-
.7\textheight},%
contents={\tikz[remember picture,overlay]{ %
\coordinate (x) at (current page marginpar area.south west|-current page.south west);
\draw[draw=none,fill=gray!20](x)rectangle(current page.north west);}}}}%
\BgMaterial}
\AtEndDocument{\thispagestyle{plain}}
}


I think I got it. Hope this helps anybody as confused with latex as I am.

Using the new pagestyle, I ended up with:

\fancypagestyle{special_chapter}{
\fancyhf{}
\begin{tikzpicture}[overlay,remember picture]
\fill [color=black!20]
(current page.north east)
rectangle
($(current page.south east) + (-1cm,0cm)$);
\end{tikzpicture}
($(current page.south west) + (1cm,0cm)$);