PfSense with Peplink Router

[macmann]

I currently have a Cisco ASA5505 acting as firewall and router.  I would like to use a peplink router and pfsense firewall.

1. What is the best method to set these up? 
2. Which one goes behind the cable modem? 
3. what do I need to configure between the two devices?  NAT?
4. When I have to port forward, which device do I have to configure to port forward?

[stephenw10]

Which peplink router?
Why use another router at all? pfSense can probably do it all.

Steve