I'm 6'6" with a long neck. Really, my cheek to shoulder is longer than average. So what works for me doesn't for others. I've never had an optic that has the same FOV from min to max. So I loosely put it in the rings/mount, with max magnification, then get comfortable behind it. Adjust the stock out and rest your cheek. Try to get in a position that your neck is comfortable enough without strain of any kind. Then use an Arisaka tool, start tightening everything down, use a plumb line to make sure you are dead nuts on. The most comfortable stock I have for distance shooting on large frame AR's, is the Battleline Industries SAPR, which can still be purchased. Even with that, I had to use the long/thicker buttpad on the Magpul to make it comfortable enough with correct LOP.