Now, the answer becomes longer since you will now have two clusters. You will either want to remove the existing one or ensure the two play nicely. It is further complicated by the means by which you installed and what services have been setup.
All databases in a cluster share the same storage location by default though you can create tablespaces and put different databases on different tablespaces. But that likely adds more complexity to the running setup than you need - at least by creating a new cluster and getting it to work properly you only need to deal with complexity during the initial setup.
