i reckon theres a sweet spot on the tanks as well, often been hit once and had 99% of health gone.
Yeah there is.
I have a video somewhere that shows where to hit it to drop the health down to 99% with 1 AT shot.
It's between the turret and the main body of the tank but from the front, not the rear.
I'll dig up the video but you can always try it yourself on your own.