How to install external libraries(PCL, OpenNI) without uninstalling related ROS packages

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Hi, everyone.

How can I install external libraries(PCL, OpenNI) without uninstalling related ROS packages
(ros-groovy-pcl, ros-groovy-openni-*, ros-groovy-navigation(which depends on ros-groovy-pcl) .etc)?
Is it possible ?

I'm trying to use ScaViSLAM(http://www.ros.org/wiki/ScaViSLAM) with Xtion PRO Live.
Unfortunately, ScaViSLAM is not ROS package, so I need to install it with this guide line(https://github.com/strasdat/ScaViSLAM).

To install ScaViSLAM, I have to install standalone pcl and OpenNI because of the difference of the version.
For example,

1. ros-groovy-pcl doesn't include pcl/io/openni_grabber.h, but standalone pcl(1.6) does.
   
2. I can use Xtion with ros-groovy-openni-*. However, when running ScaViSLAM, I have an error like "cannot open OpenNI.so.0". I think that I will not have that with standalone OpenNI installation.
   

If I uninstall ros-groovy-pcl with "sudo apt-get remove ros-groovy-pcl",
ROS packages which depend on it are also uninstalled.
If I install ros-groovy-openni-* after installation of standalone OpenNI, multiple OpenNI will be installed.
I don't like them.

If you have any idea, could you help me ?

Thanks in advance.

---Configuration---
OS : Ubuntu 12.04 32bit
ROS distro : Groovy