A more open look allows the animal to comfortably work your set. Smaller animals can't go around or through the hardwood body grip pan like they can trigger wires. Bend the trigger wires over and drill the rivet in your trigger out. Insert the screw from the hardwood pan and tighten the nut on the bolt and you're done.
 
Small=works on #110-120 Body Grip traps
 
Large=works on #160-220 body grip traps