Windows 7 SysPrep from 2nd Drive

Has anyone ever run sysprep from a second internal drive?

I am able to get the image to run correctly storing the unattend.xml file on the image itself and from a usb drive. What I need is for the image to look for the xml file on a second built in drive.

I am doing a large project with machines spread across the country so I need to automate as much as I can. There’s no budget for sending techs or new machines to each location so I have got to make this work.

Any ideas?