 Sheehan pinch squeals
It is indeed a pinch harmonic, played similarly to a pinch on a guitar, only you use your index or middle finger instead of a pick. You rest the pad of your thumb on the string you want to pinch, than snap your index/middle finger with a little bit of nail (to get an attack, if you want) upwards. If you practise it in different positions above the pickups, you'll achieve the squeal.
I got both sheehan videos, and he shows you haw to do it, and he says you can do it with any fretted note on any string in any position over the pickups!
I managed to learn it in about 3 hours of my usual practise routine, and I'm excessivly slow so you should learn it quicker!
Hope this helps,
Glenno | 
