Add ETN21 to an existing PLC

[Automationick]

Hello everyone. I'm trying to install an ETN21 on CJ1G CPU so I can put this PLC on our plant's network. I was wondering if I can install it on any available slot or I'll have to install it beside the CPU. If I install it beside the CPU, I assume the IO table will need to be changed for other modules as well. To do so, will the addresses change automatically?

TIA:)

[photovoltaic]

Slot 7 will be fine.