For me to transition back to low bar "power squats" I have to remember the following:
1) feet wider
2) toes pointed out a bit more
3) hips back first
4) keep my shins as perpendicular as possible
5) let the toes come up a bit when I'm pushing my hips back first.
Beyond those five things, I also have to remind myself "Big chest" but then be okay with the fact that I'm bending at the torso a bit more.
In the past I've always had a big poundage difference between the low bar versus high bar squats. I've been almost exclusively doing as you have, olympic training with high bar fashion, and I think that gap has lessened.
Good luck and go heavy.
All the best,