See my setup here: https://photos.app.goo.gl/VxQfWdu713vJTggA8
(Edited the link: hope it works now...)
I welded up some CRMO tubing for the pedals.
Added a 2x2 1/8 in. thick angle to the floor as a mount. (Had to add a second 1x1 1/8 angle underneath to get the required stiffness.)
UHMW bearing blocks.
Swaged a cable to the main rudder cable.
Folds down a la Flyboy. Gives full rudder travel. Removes quickly. Zip ties hold the cable to the main rudder cable out of the way when pedal is removed.
I’m not sure why your formation instructor needs rudder pedals. Stick and throttle will do the job.
*edit* I have electric flaps. My setup may be not be compatible with manual flaps.