Maus45, with these units you will be able to creep through ankle deep red clay mud if you desire with no problems. The two extra holes are easy to locate, it is explained in the instructions with photos. I do recommend that you have extra track links on hand. The units are so strong that unlike in years past where if you ingested a stone or other obstruction in your track system you would chew up expensive gears, with my system you will break a track link. Been there done that.