Header Mods

\makeatletter
\renewcommand{\section}{\@startsection {section}{1}
	{\z@}
	{\b@level@one@skip}
	{\e@level@one@skip}
	{\centering\normalfont\normalsize}}

\renewcommand{\subsection}{\@startsection{subsection}{2}
	{\z@}
	{\b@level@two@skip}
	{\e@level@two@skip}
	{\centering\normalfont\normalsize\textbf}}

\renewcommand{\subsubsection}{\@startsection{subsubsection}{3}
	{\z@}
	{0\baselineskip \@plus 0.2ex \@minus 0.2ex}
	{-1em}%
	{\normalfont\normalsize\textbf}}
\makeatother