Fancy chapter heading format under tufte-book class

Question

I want to write chapter heading for a tufte-book document.

Here is what I want to use: https://tex.stackexchange.com/a/339892/159116

\documentclass[openany,letter]{tufte-book}%
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}


\usepackage{titlesec}
\usepackage{graphicx}

\titleformat{\chapter}[block]
 {\Large\bfseries}
 {\raisebox{-\height}{\sffamily\scriptsize\MakeUppercase{\chaptertitlename}}%
  \space\raisebox{-\height}{\bigchapternumber}\space}
 {0pt}
 {\printtitle}

\newlength\pretitlewidth
\newcommand\bigchapternumber{\resizebox{24pt}{!}{\mdseries\thechapter}}
\newcommand{\printtitle}[1]{%
  \settowidth{\pretitlewidth}{%
    {\sffamily\scriptsize\MakeUppercase{\chaptertitlename}}\space
    {\bigchapternumber}\space
  }%
  \parbox[t]{\dimexpr.8\textwidth-\pretitlewidth}{%
    \linespread{1.5}\selectfont
    \hrule depth 1pt
    \vspace{3ex}
    \raggedright\bfseries #1
  }%
}

\begin{document}

\chapter{Test Chapter Heading}

\end{document}

How to make the chapter title full-width?

I think I shall add

{\begin{fullwidth}} 

and

{\end{fullwidth}}

some where in the code but couldn't figure out how.

And also, is there any way to use package like fncychap to produce fullwidth chapter in tufte-book?