I just put a set of rancho 9000's on the rear of mine. I got 1 1/2 inches shorter than stock.
I haven't driven it much yet, I ll let you know how they work at the track.
Adjustable compression or maybe comp and rebound both,with only one knob.
I have Rancho 9000's on all 4 corners of my truck with a 4" lift and they perform well for the money IMO.. QA1's could be ordered to fit your application and would be a superior product in comparison but at a substantial increase in cost,,,, is it worth it?? IDK