Host networking setup?

[cr08]

So I've been trying to wrap my head around this one. Particularly on the networking side. Currently have a debian box with 2 NIC's installed and looking at installing pfSense in a virtualbox VM on top of it. Got everything set up as I want it as far as having the VM start and stop if for whatever reason the host needs to be taken offline, raised cpu priority, and VM tweaks to lower cpu usage as noted elsewhere in this forum.

But the part I am getting confused on is the networking side of it. My intent is to have eth0 on the host be the WAN and locked to the VM to where the host cannot bind to it. And pfSense should be able to pull a DHCP address from my ISP rather than some weird double nat setup. eth1 on the host will be the LAN but the host should be able to use this as well in a sort of bridged mode (The host OS can route to the net through pfsense and access other LAN machines while pfsense does its thing routing both the host OS and other LAN machines. If that makes any sense. oO).

Any suggestions how I can go about this? Thanks.