try to install php 5.6

Hello

i try to install php 5.6 its conflicting with prvious version . how could i prevent this?
if i remove old version of php and install 5.6 should everything on plesk work ahead?

# rpm -Uvh https://mirror.webtatic.com/yum/el6/latest.rpm
Retrieving https://mirror.webtatic.com/yum/el6/latest.rpm
Preparing... ########################################### [100%]
package webtatic-release-6-6.noarch is already installed

# yum install php56w...

try to install php 5.6