[dnanian]

Of course, before sending off the eMac, you'll want to boot from the backup to make sure the backup itself is working as you expect it to. Make absolutely certain you used "Backup - all files" as the script!

When it comes back, you'll boot from the external drive. Use Disk Utility to erase the new drive (make sure the partition type, using the partition tab, is "Apple Partition Map"), and then simply use "Backup - all files" to copy back. Give the drive the same name it used to have

That's all there is to it!