This is one of the reasons that MS advises against using share permissons. You're supposed to leave them open and use NTFS ACLs to restrict access at the filesystem level.
Originally posted by: NogginBoink
Use ntbackup or robocopy to copy files with permissions.
Export HKLM\System\CurrentControlSet\Services\LanManServer\Shares key and import to new server to migrage shares and share permissions.
Go to lunch early from all the time you saved doing it this way. 🙂