Airbox

i'd check it out.....depends on how big the holes are and how many.....but i'd definitely do a chop to be safe
 
Just take the lid off completely, unless your going through 4ft deep mud its a huge restriction. Go up a size on the main do a plug chop and see were it puts you, depending on altitude and other mods you may need to bump up the piolet too... But I never had too.