How to access 2nd TM804G

Hi, Optimum installed 2 Arris TM804G's. I'm able to access the 1st one by pointing a browser to 192.168.100.1. I can confirm it's the first one by comparing the MAC addresses against the label on the modem. My question is, how do I access the 2nd TM804G? Does it sense the IP address conflict and assign itself another address? If so, which one? It's not .100.2 Thanks.