there's actually 3 points to unbolt - the one you need to remove is the "upper pedal" to free the part that goes thru the floor from above, the rest can stay on the mstr cyl util you get it out - see
pic at bottom of this page that the main one right below the floor you'll need to leave the nut on and use a BFH on it or turn the pedal arm above with a pipe wrench - the eccentric one is usually siezed [called "adjusting bolt"] from fluid dripping on it - the "lower arm" right at the mstr has the keeper plate, doesn't even need to come off unless you actually replace the mstr
Bill