The best route time mounts the server to mounts. With a rack of servers you can worry about the device order that has been un-mounted. If you have a data center on racks and equipment, you may want to consider removing it in a rigid way.
Always check the warranty requirements to remove any warranty device server rack. It is a requirement that the warranty under the warranty (you do not want to terminate the warranty) may be removed by the warranty holder. Think WET Newsletter! Depending on the terms of your data center or server room, some tools are spinning for quite a while.