General Questions

I have an office with 2 company in it.  They both share some servers (postfix) but the time has come when I need to point port 443 to each server so I need multiple wan IPs.  My question is can I go:

DSL > Monowall > Switch > Router 1 (WAN IP1), Router 2 (WAN IP2)

How would I set this up with a mono wall...

You will need more than 1 IP address from your ISP, as you need to forward the same port to 2 different servers.  The easiest way in your scenario would be Proxy ARP.