Port mapping a high port number to an internal workstation.

Hope this makes sense... Have a P2 300 SuSE 8.1 server, that is also the firewall machine and dsl router, and have an internal workstation with Flight Gear running Jpeg factory on port 2003, how would one connect from an external website to see the pictures being displayed? Is it liste as a dmz? I would love to put a link in my website at linuxsimulations.org that goes through port 2003, this should show a jpeg picture of the aircraft flying (or whatever. Which is the best way to do that? Thanks, Matt