The Wirblewind, Ostwind, and M16 are very easy to damage. IMO, it is too easy. Even the Oscar with its paired .50 cal MG's can turret any of those three AA platforms well enough. Just get enough shots on target and "puuf".
I have yet to not have a hit from my Stuka G-2, Hurricane IID, or IL-2 (I use 23mm), not disable the turret of any of those three. The same goes for most every other fighter I've used as well. Just get the shots in to the turret and that is all it takes (need to hit the gun). I have hit the turret armor while in low angle shallow dive and not disabled it, but that has to do with the armor doing its job and not getting enough shots on target.
The thing with the Stuka G-2 and Hurricane IID (and ultimately the IL-2 as well), is to be patient and take only accurate shots. Get the convergence to 275 or 300, and WAIT until you have a good gun solution on the target. Don't bother firing at 600 yards unless you're in the IL-2 with plenty of ammo and you have the "spray and pray" mentality with the goal of damaging a turret and not destroying the vehicle instead.
Shot for shot, I've found the Stuka G-2 to be the most effective at busting tanks. I don't know if it because of the projectile composition or the weight/velocity thing, or both. Maybe it could be an accuracy thing, trajectory related, I don't know. Finding actual data or rather the correct data on the German BK 37mm is difficult, I'm not sure which ammo it is using either. Is our G-2 using the APCR or regular AP?