The MAC address on the sticker on the bottom should be the one for your WAN connection, you can verify by looking at the Status > Device Info page when you log into the router.
Well it's not, the only way I've been able to set up my DHCP is to clone my computer's mac in manual setup under the Internet tab.
When I tried to enter the Mac addy , save , reboot I will net be able to reach my ISP.
UPDATE: After I entered the routers mac, saved, rebooted. I reset the cable modem and that did it. It kept my routers mac in wan.