Well, basically just repeat what you did for the first one.
You should have (in /etc/sysconfig/network-scripts) a pair of files ifcfg-br0 & ifcfg-eth0 that work as one.
Just repeat for ifcfg-br1 & eth1 if you want the 2nd VM to use a different physical NIC.
Note, I haven't tried this (only have one NIC), but it seems logical to me.
Alternately, wait for someone else to come along who has done this
or ask google.