By the (lack of) virtue of the Girls Und Panzer Der Film not having a Nightmare Fuel page, The Reveal of the University Team's Mörser Karl, which can't even be called a tank (both in and out of universe), but more of a BFG on wheels. The force of impact from its shells alone is enough to knock lesser tanks clean off the ground! The fact that this is a sport and that you'd have to go out of your way to actually get hurt (and someother stuff) does nothing to make the resulting explosions less horrifying.
If you are looking for some Rule 34 material of G&P, do not even try Takotsuboya's doujin manga. It twists every piece of setting to create a senseless bloodbath, apparently because real WWII is not dark enough. Seriously, Pravda has mass graves? Kuromorimine has concentration camps?
The tanks in the doujins don't have "non-penetrating shells" or "carbon-lining protection". No, if a tank gets penetrated by another, the tank blows up in a fiery inferno, with the girls still in it.
Limitation on weapons existing in GuP are also lifted, we have girls with sniper rifles hunting down the tank girls, flamethrower tanks torching exposed crew members, Nazis executing prisoners with machine guns, Katyusha rockets barrage enemy lines, anti-tank weapons used by infantry (with associated risks). Note that we haven't changed the fact that the combatants are all still school girls.
If all that above wasn't bad enough for you, Uziga Waita has done a work on the series. Yeah, the most infamous guro hentai artist in Rule 34. We'll leave the rest to your imaginations.
Takotsuboya's doujin series also drives into the Adult Fear, Psychological Horror and Fridge Horror sections of Nightmare Fuel in Girls und Panzer. What sort of high school girl would participate in a blood sport? Answer, none. They were tricked into that style of Senshadou combat. Imagine sending your daughter into what you thought was American Gladiators only for her to be thrown into a pit with a hungry lion. That is what the Senshadou Federation's Bait and Switch on the rules essentially did. No sane girl would actually practice Senshadou otherwise. Why would these girls kill? It is simply to avoid their own death. What happens when you hesitate? You die. What sort of casualties does this produce? Total. Kuromorimine's past year team only has two survivors and they were last year's finalist. Ooarai's winning team has just one survivor. Basically dozens of girls are expected to die in each match. Senshadou is simply not sustainable as a voluntary sport without the massive Handwave that protects the crews from the Nightmare Fuel aspects of their sport.