Can't install Norton System Works with NIS 2008

A few months ago I purchased both NIS 2008 and System Works (no date on the box).  I cannot install them both on Windows XP.  I had them both on the year before but couldn't get them to work.  System Works is still in the box and I really want to install it.  It costs 60.00!!!  What do I need to do to install this.