ive bent quite a few pairs of fks brakes in my day...its an easy enough process.
to mount, wrap an elastic band around the brakes tightly, and make sure that the elastic is over the plate in the back. once theyre mounted up, take off the elastics. theyll be sitting on the top sheet of the ski at this point.
grab one of the many broken ski poles youve undoubtedly accumulated through the years and stick the end of the brake into the open end of the broken pole. then, use ya muscles to bend 'er out, almost all the way. do this to the other side too, unless youre into one brake like i got on a few pairs.
once theyre sticking out of the sides like a flying v from mighty ducks, stick something between them and the sidewall. most recently, i used a folded up paper plate, but some kind of cloth tends to work better. once you got it in there pretty good, use that ski pole again, put the brake like halfway into the pole, and bend. the sidewall of the ski will act like the lever to bend the brake, which is why youll want to have something in there so you dont mess up the edge or sidewall. bend until the brakes fall vertical again, and viola! your brakes will look just like the ones that come with the wide brake fks', and you wont have to spend an arm and a leg buying them.
enjoy!