[CentOS] newbie question on installation over existing Linux

If I choose to do a fresh install of CentOS 6 with "replace existing
Linux systems", will it also wipe out my /home directory? In the past
when I've done this with another Linux distro, /home was not affected.

Or, would I need to do "fresh" install and then muck with partitioning
using a Custom Layout? Right now, it's kind of looking like the latter
to me, and if so, will I lose data?

I spent some time on the Forums and reading the RH documentation, but,
no real answers to this specific question.

Thanks for any help.
-- 
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MzK

"We can all sleep easy at night knowing that
 somewhere at any given time,
 the Foo Fighters are out there fighting Foo."
                          -- David Letterman