\documentclass[12pt, letterpaper]{article}
\usepackage{fullpage}
\usepackage{palatino}
\usepackage{color}
\usepackage[T1]{fontenc}
\usepackage[utf8]{luainputenc}
\usepackage{gregoriotex}
%\usepackage{parskip}
%\usepackage{changemargin}
\pagestyle{empty}
\begin{document}
\newcommand{\red}[1]{\textcolor{red}{#1}}
\newcommand{\black}[1]{\textcolor{black}{#1}}

%\setspaceafterinitial{3.2mm plus 0em minus 0em}
%\setspacebeforeinitial{3.2mm plus 0em minus 0em}

\def\greinitialformat#1{%
{\fontsize{43}{43}\selectfont #1}%
}

\setgrefactor{17}
\grespaceabovelines=5mm

\begin{center}\begin{huge}\textsc{}\end{huge}\end{center}

\includescore{GoodFriday4.-full.tex}

\end{document}