Bridging actiontec gt784wnv

Has anyone had success bridging their actiontec gt784wnv verizon modem/router to the Pepwave SOHO?

I logged onto the modem/router at using an ethernet cable connected to the modem/router and PC.

I then clicked"RFC14F3 - transparent bridge mode" I then connected the SOHO and when I try and access the SOHO via its says wrong password/username. I have a reset the router and still can not access the SOHO.

The default credentials for the SOHO are admin & admin for both.