How can I resolve an issue where I did wrong uninstall of Couchbase

Hi There, I accidentally installed a wrong couchhase version in my linux. What I did was just to go to /opt directory and removed the whole directory and removed entries from /etc/rc.d/init.d. I did not follow whatever described in your docuemntation due to my lack of experience. So when I try to install a new version, it will tell me it is in conflict with the previous package. So I try to install the old one that I removed, thinking that I might trigger the system to install it again and then i try to uninstall it. But forturnately I got this couchbase package is already installed. So there got to be some file that registers this installation, anyone can point to me the option on how to remove this package of the old couchbase installation?
Your responses are greatly appreciated!