Where clown hunting is concerned there’s no such thing as overkill. That big bull clown you see stuffed and mounted in the Museum of Natural History was taken out from the air by an AC-130 gunship (which was badly damaged by several direct cream pie hits).
According to Wikipedia, a 1.6" thickness of a ceramic called aluminium oxynitride can resist .50 BMG rounds. IOW, a transparent substance with more penetration resistance than many grades of steel.
A round (be it .338 or smaller) doesn’t need to pierce the passenger compartment on its’ first shot although it probably would, all a serious round has to do is stop the engine, which a couple of well placed rounds would do. Once the vehicle is immobile, the sniper can pick it apart until a weakness is found.
You might be able to strike it across the front through the rad but that puts you straight in front of the vehicle and I’m not sure if there is additional ballistic protection other than the strakes across the front. If it’s the uparmoured version I think I’d want the above mentioned NTW-20 to make sure it’s immobilized.