symmetrix dmx - 3 bay rack disassembly

I have a symmetrix DMX that is made up of 3 racks connected together. I am trying to determine how to separate the racks so they can be decommissioned however my Dell Rep is saying that they do not come apart.

I know that is not possible as there is no way they could have been put into the building unless they are separated. Does anyone have any information about how the racks come apart?