CARP Entire Network

[TheGeek]

I know that CARP VIPs do not support entire networks.
So my current setup has only 1 node allocating the WAN network with a Proxy Arp.
I read this https://forum.pfsense.org/index.php?topic=45209.msg240929#msg240929 but i don't understand how i am supposed to set it up, and which IP i will set as CARP, since i cannot create a CARP network.