DG3450 mac bridge and moca

I have a DG3450 and I use its moca network for some tivo devices. I'd like to use my own firewall/router & wifi access points but keep the moca network. If I put the cable modem in bridge mode I understand I would lose the moca networking. Could I do a mac bridge to my router, run my local wired and wifi from that and keep the moca network on? I figure I would only have one IP address from my isp and it would go to the router. I need to allow the moca tivo devices to access the internet and they need to get local ip addresses by dhcp. Can I set the Arris to work as a dhcp server for the moca and use 192.168.1.250-192.168.1.255 range to keep from conflicting with my wifi? Would this work? The alternative is completely bridge the cable modem and buy a moca bridge.