JDS,
Ibex here in NM are about the size of a full sized German Shepard Dog and you have about 11 inces from shoulder to brisket. I was fortunate to draw the rifle tag my first year that I put in for this hunt. I had never seen them before and I really had no clue as to what they looked like until I drove down to see them. Their horns make them look a lot bigger than what they are. Good luck. If you get a chance look at some pictures on kauffmanoutfitters.com he is an outfitter here in NM and he has a picture of my billy on the website. I also have the picture posted on poleocreekoutfitters.com this is my brother-in-laws website.