Torso Fit and Pack Adjustment Guide
As promised here is a guide for proper torso fit and pack adjustment. Once you have familiarized your self with torso fit and adjustment guides you will find the Hellcat has ALL the modern adjustments that are common on todays commercial packs. First read these links to REI's backpack adjustment guides
Points of reference for torso adjustment should be the notch ( C-7 ) at the top of the shoulder pads and the midpoint of the hip pad( line of iliac crest). Remember these are just references; but I believe they will get you in the right ball park.
Loosen the side and torso attachment straps...you don't have to remove them.....measure your torso length; move the shoulder straps up or down accordingly and retighten the attachment straps. EDIT I have another comment here and I have added a couple of more pics. You must also loosen the load lifters significantly for torso fit. I just recently fit my 10 yo (Webelo II) and his torso length was 14 inches. No surprise it worked fantastic. The bonus for him was we were able to use the second set of side attachment straps and the load sets higher for better balance. The beauty is this adjustment can be reset as he matures, giving him use of the pack well into his adulthood(the Hellcat will probably outlast him)
You should now be fitted for torso length. Readjust load lifters; sternum strap; hip belt and tweak lower adjustment on shoulder strap per the REI guide. The next two pics show the difference in height of shoulder straps and load lifter straps. The top pick is mine set at a torso length of 18 inches; the bottom pic is of my 10 yo's set at o torso length of 14 inches.
In case you didn't know these are the parts refered to in the REI article "adjusting the fit"
Shoulder strap adjustment
Stabilizer strap.... notice it is not on the kidney belt.... it's the strap I told you not to tighten until the ruck was loaded
Quick release... most of us will never use this other than for convenience during assembly/disassembly
Now you have it; all the tools for proper fit and load stabilization of your Hellcat.