Check out this article which describes how to use WinPE 3 in your Ghost environment:
https://www-secure.symantec.com/connect/articles/creating-and-using-winpe31-image-gss-251
This enables you to use Win 7 drivers.
Also, be aware that Ghost Solution Suite 3 is in active Beta and should be released in the next few weeks. This will allow imaging of UEFI systems and use the latest WinPE version as well.