Bounding box in part coordinate system

I've been using the Bounding Box macro by Wayne Tiffany (http://www.solidworkstips.com/macro_pages/downloads/BoundingBox.zip) for my own parts and it's great.  I always model my parts to be in line with the Global XYZ coordinate system.  I've gotten a ton of (imported) parts from a client though who models his parts in the machine coordinate system so they might be located many feet from the origin and at some strange and arbitrary angle.  These parts are all freeform surfaces with no flat planes to speak of.  Is there a way to modify Wayne's macro to determine the smallest possible bounding box?  I would expect that to make the box line up with the part coordinate system rather than the machine coordinate system. 

Thanks in advance.

SolidworksApi macros