You can easily make the conventional four or six fletch big feathers from the full length feathers if you like that kind. Otherwise, just take a full length feather and grind it down so the base is thin enough to easily wrap around the shaft. I fletch everything almost exclusively with full length feathers and burn em. The Tru Flights I use always need some grinding before use.
Way I grind them is to take two blocks of wood about as long as the full length feather put the feather between with the base protruding and commence to sand it across a piece of sandpaper that is on a flat surface. You can vary the pressure on each end to get it even.
I start at the nock end and just glue that end first and clamp it for a good long dry time. From there it's easy to wrap it around the shaft and then clamp the front the same way.