Help with Box Squat

I’m so used to squatting with the high bar position but I keep reading articles and opinions saying that the high bar position just does not give me the full benefit of doing the Box Squat. Even from videos and images I still don’t get it, is the bar supposed to be on the area right under my shoulders? Wouldn’t that put the weight right on my spine?

I’ve gone through a little trial and error and put the bar a little below the edge of my shoulders but that feels so awkward and I can never seem to finish my heaviest set without failing (but with high-bar, no problem). My left hand and shoulder feels pretty strained too, is this due to lack of shoulder flexibility? I’m already doing dislocations and doorway presses every day just to get a better feel for the low bar position.

SAGES, ADVISE!

No matter how low the bar will go, it’ll still be on your traps, providing they’re thick enough and your back is packed tight. Don’t worry about your spine.

Thanks to the mod for the edit.

And thank you for your input too, phil.