Upgrading from Office Home and Student to Small Business

New notebook because old one crashed. I have my installation disks of Office
Small Business 2007 UPGRADE, which was installed on the old notebook. Of
course, I can't locate the disks for Office 2003, which I'd upgraded from.
And, of course, in the install process, Office 2007 is telling me there's no
version of Office on my computer so I can't "upgrade."

I do, however, have the install disks for Office Home and Student 2007
(which is loaded on a different computer). According to the Office Small
Business Upgrade docs, that qualifies as a version eligible for upgrade.
When prompted to insert that disk during the Small Business upgrade, I'm
told to navigate to the "appropriate drive." But the install process tells
me the path I've chosen doesn't point to a qualifying upgradable product.

I've tried pointing to lots of different locations on the underlying disk
but haven't hit the right one. Where should I point?

(I suppose I can install Home and Student and then upgrade from that full
install, but...)

Thanks,

Ken Isaacson
SILENT COUNSEL, a legal thriller
www.KenIsaacson.com