How do I get separate SSIDs for 2.4ghz and 5ghz on Fios G3100

[#1]

We recently for Gigabit and have a G3100 router. By default it has one SSID (Fios-xxxxxx but I changed it to "speedy") that has both 2.4 and 5ghz on it. I cannot seem to find out on myfiosgateway.com where I would go about making these two separate SSIDs (ex: speedy2.4 only working with 2.4ghz and speedy5 only working with 5ghz). Is it even possible on this router? If so, how do I do it?

[#2 · Accepted solution]

You have to disable SON first. 
Go to Wireless Settings/Advanced Security Settings/ Other Advanced Wireless Options/Self-Organizing Network Enabled and set to Off

Then under basic settings you have to rename the 5G SSID. 

[#3]

If you rename the SSID, will FIOS STB's still work?

[#4]

Yes, the set-tops will work fine.  The FiOS routers create a completely separate, hidden WiFi network for the FiOS ONE set-top-boxes.  SSID changes do not affect this network.

[#5]

the "off" button is greyed out.  How do I separate the networks.  Half of my devices won't connect to 5g.