I was thinking bolt one side of the hinge to the floor and loosely attach the other side to the pedal (so it can slide, but not flip back). I had not thought about doing it the opposite way.
Is the heavier spring tiring?
No, not all, especially with the ability to hold my foot flat on the floor as opposed to having to have it hanging due to the awkward OEM foot pedal angle. The heavier spring alone was an improvement simply for giving better feedback on pedal movement and position.