Head to the hardware store with a pedal, and find some longer bolts that will fit the holes. Also pick up nuts to fit that will stack to the length you need. Thread em onto the bolt with clip attached, then secure to pedal with remaining nuts (don't forget washers!). I love ghetto-rigging things like this. I did it once in a pinch by disassembling a U-lock carrier and pulling the screws out of it.