regards replacing for OEM, i had the nearside hanger off to get the pegs off to put a new gear shift lever on...
The HEX bolt was tight as hell but with a vice and some heat from camping gas torch it started to undo, not sure if you will have issues if they have been changed as mine had not been touched since production...
Have not taken the offside hanger off but the foot peg is still held in place via a HEX bolt throught the hanger into the back of it, also you will have the rear brake light switch and read brake master cylinder to deal with....?