Configure a router with DD-WRT for dual-WAN with failover

I have a TP-Link TL-WR1043ND router with dd-wrt installed ( ***SVN revision* 16994**) I need you to research exactly what should be done in order for it to support dual-WAN with failover. You can start with [login to view URL] but this article is with examples for a WRT54GL so I guess that various tweaks should be made. After you are confident you can carry out the configuration successfully, you should send me the detailed instructions and I'll give you remote access to my screen while I configure the router according to the instructions - in case any real-time changes are required. If you require any prior information, such as the output of various commands on the router, I can easily ssh into it and send such outputs to you.