To move IIS to a different drive is a fairly straightforward procedure.
This blog – -> http://blogs.iis.net/thomad/archive/2008/02/10/moving-the-iis7-inetpub-directory-to-a-different-drive.aspx has detailed the steps very neatly.
In a nutshell, and to adapt them to a SharePoint install, here is what I recommend.
1. Run the SharePoint pre-requisite installer and say no to running the SharePoint products and Technologies Wizard.
2. Run the MoveIIS7root.bat from the site above
3. Use xcopy to copy all content to the new location
4. Verify that E:\inetpub was created, and verify ACL’s and content with what is on C:\InetPub
5. navigate to HKLM\Software\Microsoft\InetSTP and make sure physical path to IIS is set to the path you selected when running MoveIIS7root.bat and verify that it does not contain two \\’s. it should read e:\ not e:\\
6. Verify that you can delete the C:\InetPub folder, and if you can not, then take ownership starting at the deepest directories and work your way up to the C:\inetpub, deleting as you go.
7. Stop and start www service (sc stop w3svc, sc query w3svc, then after is stopped, sc start w3svc – or via services.msc)
8. Stop and start IIS admin service (sc stop iisadmin, sc query iisadmin, sc start iisadmin)
9. Restart server, make sure recovery settings for services are set to restart on failures
10. Continue with the SharePoint install by running the SharePoint Product and Technologies Wizard