Thats pretty much it.

First I dismantled it and stared at all the parts for a few hours. My first attempt was to simply extend the arms with a wooden strip, but that didn't work as they have to have play to compensate for the up and down movement, so then I cut off the ends of the swivel arms (the part with the guide groove) and inserted the extension in between. It increased the width of the pedals by about 33% - so they're no longer "nut crackers".







Now I just have to figure out a nice way to enclose them.