I felt the problem ,when I was practicing yngwie 's ascending lick and Eric 's fives. As I am naturally an upward pickslanter , I had a hard time learning downward pickslanting.It didn’t worked naturally to me.I can rotate my hand to play downward pick slanting when I am playing scales and sequences ,since the amount to do dwps in scales are minimal. But it seemed impossible to play dwps as a whole throughout a lick.
So without wasting any time, I started to reverse the pickstrokes of even number of notes per string licks and learned to adapt with dwps licks , and it worked very well.I only had trouble figuring yngwie’s volcano lick and Eric’s fives licks, both had downward sweeps which I find difficult for upward pickslanting. Please post any solution.
Peace
Lower your hand. This way your pick will be way more likely to be in DWPS position. And use rest strokes to verify if your pick is slanted enough.