The "Article" module framework makes it pretty simple for cloning a module.

To make a clone

Step #1: change all template file names under /templates/ and /templates/blocks/ starting with "article" (new module dirname). For example, change article_index.html to newarticle_index.html

Step #2: edit file "include/vars.php", set the value for $GLOBALS["ART_DB_PREFIX"], for say, "artdb"

Step #3: edit all mysql files under /sql/, change prefix value of all tables to the specified value "artdb". For example, change "CREATE TABLE `art_article`" to "CREATE TABLE `artdb_article`"

Step #4: install the cloned module as regular