Firewall/NAT

I just got monowall setup, and have pppoe connectivity, yay..

I am upgrading from a little WatchGuard SOHO6 hardware based firewall. That firewall used "Managed VPN" to connect to a WatchGuard Firebox- the Managed VPN only had a few basic settings.... DVCP address, client name and shared key.

I am now trying to set up an IPSEC firewall from this monowall into the FireBox - but can't figure out how... Are there any whitepages or something that get into more detail, or anyone with similiar experience?

thanks!

I just noticed I posted this in the wrong category, if someone could move it I'd appreciate it! thanks