RE: You are on an unguided hunt and
Manboy---Yes it's in the vicinity you've described. Just remember it's pretty much under the spine but hugging the side of the ribs at that point. Once you squeeze your hand in the small squishy slot you'll feel it immedieately. If you've ever taking the tenderloin out of a gutted animal think back and remember where you cut it out of, it's just under the spine and to the rear of the animal.
I too like a solid pack-frame. Not saying it's the best there is, but mine are very comftorable to use and I've taken out close to 60 elk with such packs. As I mentioned earlier, I would not reccommend carrying in a cumbersome pack on an elk hunt where you're planning on covering tons of country. For me, they're just in the way. Sometimes certain encounters require one to move swiftly into action, when this happens, and it does a lot, I want to be ready to go on the drop of a hat and not worry about wrestling an over-sized pack around. This is what has worked for us. Plus the country we hunt is very rugged with tons of downfall, carrying lite, is a good thing!!--------ElkNut1