Bridging with 2wire 2701HG-S DSL modem
Sasktel has installed a 2wire 2701HG-S to provide DSL service for me. After quite a bit of messing around, I believe I've figured out how to make it act like a bridge instead of routing with NAT. The instructions from James Hartig on how to use the DMZplus feature are key.
The short version is to use the firewall menu to mark your own router as the DMZplus device. As far as I can tell, the 2wire device uses the MAC address of the second router to bridge traffic (layer 2 bridge?). Your router can use DHCP to get the WAN IP address. I care about latency so I don't want two layers of NAT. The 2wire device is fairly flexible but not like OpenWRT or DD-WRT, etc.