And don't forget you need some sort of signal level shifting between the Arduino outputs and the module's inputs. You would probably get away with not level shifting the signal from the module back to the Arduino.
I do not know if the Arduino library for these modules will work correctly with two modules connected.
While I have not done this on the Arduino I did do this on the Raspberry Pi, the principle is the same.
See the video at:-
what is the SS pin for
For selecting what reader is enabled. SS stands for Slave Select. It is placed low on the device you want to read / write - from / to. And high on all the other devices you want to be disabled.