Can't the package be added as "tomcat8" similar to what you have with tomcat packages vs. tomcat6 packages on RHEL/CentOS 6? The problem is that tomcat 8 is not available in RHEL/CentOS 7. I have several projects that need a tomcat8 install. I've already submitted a feature request to Red Hat to try and get tomcat8 added to Software Collections 3.x. They only avenue right now is to add JBoss Web Server, which incurs additional pricing.