[Tex/LaTex] Conversion of tex to latex

Question

Quite surprisingly for me, I did not find valuable information on how to convert plain TeX files to LaTeX documents. There is a TeX.SX question, but it was answered with a particular solution.

I have a larger number of simple TeX files with equations which I would like to convert to LaTeX articles. The need arises because I want to merge the documents with others which are based on LaTeX. The files do not contain any images and no complicated layouts.

Is there a simple but stable conversion tool somewhere out there which helps me to achieve this?

There seems to be a tool called tex2latex but I only found a windows binary. I work on Ubuntu and my LaTeX distribution is TeX Live.

Answer 1

\documentclass{article}
\usepackage{plain}
\begin{document}
\begin{plain}
\input{texfile}
\end{plain}
\end{document}