Yes, you can. It's simpler if people just don't remove Office 2004 when
they install Office 2008, but you can re-install 2004.
Two caveats:
1) you cannot run both Entourage 2004 and 2008 at the same time.
Entourage you MUST pick one and stick with it. If you choose to rollback
to Erage 2004, it requires some preparation and backup. Otherwise, you
can happily have both Word 2004 and 2008 launched at the same time, and
I believe the same is true of Excel and PPT.
2) Office 2008 handles fonts differently---Office 2004 used to dump all
sorts of fonts into your user library the first time a user account ran
it. Installing Office 2008 over 2004 moves those fonts into a Fonts
Disabled folder and replaces them with newer versions of the fonts which
are stored in the hard drive library.
To play it entirely safe, you could remove Office 2008, install Office
2004 and re-install Office 2008.
But I think it's worth a simpler experiment--install Office 2004, launch
an app and let it do setup. It will copy a whole bunch of fonts into
username/library/fonts. Quit all office apps, then create a
username/library/fonts disabled folder and move all the fonts from
username/library/fonts into there. I *think* that might work--it might
create problems *if* the Office 2004 installer had been smart enough to
look for fonts with the same name and do something to move the Office
2008 fonts, but let's hope the Office 2004 installer is not that smart.
Since fixing any problem caused by this would be removing and
reinstalling from scratch, it's not that much more time to test. Your call.
