replace Brocade FC swtich (3900 -> 5000)

I have a 6140 connected to two Brocade FC switches.  One switch is a 3900 and the other is a 5000.  Each server has two HBAs, one connected to each switch. I need to replace the 3900 with a second 5000.
It looks like the 6140 has unused FC connections.  It is reasonable to attach two of the unused connections (one from each controller) to the second 5000 and move the servers – one at a time – without requiring an outage?

Thanks,
GlenG