They seem to be pretty tight with their tech data, but they aren't as crafty as they think! You need to configure the 2701HG as a bridge, and that's not actually much of a problem. First, download
the manual/user guide for your device. (The
installation guide couldn't hurt for reference...). Now, on page 113, it tells you about bridge mode and how to set it up. You may need to read much more of the manual to see how to get to those settings, but you'll have all that data handy. You may also need the
activation key code to get at the advanced settings.
Once the device is set to bridge, I can't tell you which of the four Ethernet ports will be where to connect, but I'd suspect that either port 1 or all of them will work for you.
When you get it set up, let us know how it went.