How do I connect DAGR to SINCGARS?

I know that Rockwell Collins makes a cable that goes from com port J1 or J2 to the front data port on the radio and I know how to set up the RT-1523 to recieve and use said data. What I need to know is can you use a DAGR for both the SINCGARS and a BFT/JCR? Also on the newer VAA's there is a port on the front (J12 I think) that is labled GPS IN, is there a cable that can carry data from the DAGR to this port on the VAA and to both radios or is it just used for the EGR on some of the E/F/G models?