Who are you trying to hide the upgrade from?
Anyways, you will need to 'map out' the front panel connectors as they will not match up to the layout used in generic motherbds. Plan on having to move the wires to standard 2 pin connectors. USB is usually still the same pinout. The power supply could be replaced with a standard sized ATX in my similar case but you probably won't be able to reuse the old one.
Whats the goal of rebuilding? What are you going to use it for?