Need Help Mirroring plans in autodesk building sys. 2006 !!!

[Toby ACAD]

I just finished a project (Electrical Drawings) And the next building going up is the exact same building only mirrored exactly over the middle of the plans. I'm trying to just find a point on the drawings, mirror it over and all my text/blocks will work out, just that easy lol.. I know there has to be a way to mirror an xref right ?? Thanks in advance :)

[ReMark]

Take a look at this as it appears to be about the same topic:

http://forums.cadalyst.com/showthread.php?t=2635