I've never destroyed T-34's with IL-2 or Hurri2D guns. It seems the T-34 is extremely resilient against field guns or aircraft guns. I've seen Tigers and Panzers get damaged by concentrated 37mm fire from field guns, and get detracked or engine dead due to aircraft fire, but I've personally never seen the T-34 suffer such damage.. man, the Soviets made a hardy tank.
However, when it comes to Panzers I've destroyed quite a lot of them with Hurri2Ds.
There seems to be two key methods to killing Panzers:
One of them is diving down at the Panzer at a steep angle and going for the rooftop. I admit I'm not very good at that. It takes good flying skills and gunnery to hit such a small moving target at such steep angles.
The second method is much easier, but also has more danger of being intercepted by enemy AA fire, especially if the target tank is escorted by Osties or M16s. Approach the Panzer, fly very low, almost parallel to the ground, and let out 3~4 sets of 40mm fire to the rear of the Panzer. The target zone is usually the engine quarters and the point where the chassis meets the turret. If the multiple barrage of 40mms connect at a single spot it will explode the Panzer with a single pass.
Killing Panzers with the Hurri2D isn't all that hard. I think the hardest part of tank strafing is actually coping with the extremely angled terrain of AH2. There's never a flat plain when tanks approach the town.