For this type of task, the Process -> Interpolate tool works perfectly.
It's a two-step process: first you select the events and then choose what you want done to them. You'll need to do it twice, first to set everything >= 64 to 127 and again to set everything < 64 to zero.
In the event filter dialog, un-check everything except "Control", then set both Min and Max values to 64 next to "Number" to specify pedal events. Next, set the "Value" Min to 64 and Max to 127. Click OK to select all the pedal events with values between 64 and 127.
In the Replace dialog, set the Min and Max values to 127 and click OK.
Now repeat the process, except this time use Min = 0, Max = 63 in the selection dialog and set Min = 0, Max = 0 in the Replace dialog.
All your pedal events should now be 0 or 127.