Thanks Waku.
Just finished with the exercise, basically it is quite an easy operation to replace the force springs. They are located 1 big spring in each pedals red pistons with different force, just needed to replace those ones. Olny thing is til you reach them you have to unscrew totally 24 screws... lol
So it is quite easy, just time consuming.
But i got my loved bigger brake pedal force on the left pedal, so i am happy!