[arch-general] Installing php 7 and php56 at the same time?

All, I need to downgrade php from 7 to 5.6. I built the 5.6.19 package from AUR and I'm now at the install stage. Before I do I thought I would ask if I need to remove php7 before installing php5.6? The PKGBUILD has no 'conflicts' or 'replaces' specified and they are prefixed differently (e.g. php and php56), but what I am unclear on is how my applications will know which one to use? This was necessitate when php7 broke part of my groupware package (webdav/caldav/carddav) that I need working until those can be upgraded. Do I just install php56 along side php7 or remove php7 first? If removed, then I set IgnorePkg in packman.conf -- David C. Rankin, J.D.,P.E.