SBS 2003 SP2 VPN Setup and config with external DSL router

I am trying to setup and configure remote access for the users and for remote support of the SBS Small Business Server SP2 (Not R2) Running on a Dell PowerEdge 800.

This is a small company with 5 users.

I have an external DSL router (Netopia 3347W) provided by AT&T and have the Statip Address to configure but am reluctant to "mess-up" the network as it is working just fine for email, Internet access. The Netopia router is providing the DHCP IP addresses for the LAN.

I would like to configure the Netopia wi the statip IP for remote access, but maintain the internal LAN addressing.  IS this possible? How do I do this?

Any ideas??