Stack 2 N1108 switches

I have 2 N1108EP-ON switches and would like to stack them using the SFP+ ports.  I see in the manual for the N series switches that it can be done on the N1100-ON series, but I can't find what exactly I need to do.  I'm assuming I can use 1 gig fiber transceivers, but what commands would I need to use to specify the ports.

I tried:

config

stack

stack-port gi1/0/11 stack

But this did not work.  Can someone explain to me how to stack the N1108 switches?