I haven't used them, myself, but the cheapest and simplest way that people raise the pedals is with a block. Do a google image search for "clutch pedal extender block" and that should steer you in the right direction. 
Sorry to hear that. I didn't know of any Fiesta-specific pedal blocks, but conceptually, it would be the simplest way to achieve what you want. If you find something that works, please update us, as it might help someone else here, too.Edit: the pedal extension for the Mustang does not fit the Fiesta.|