How to clean rust on under side of hood



I’ll try to make this short. A couple months back the water pump on my Chevy Truck had a really bad leak, I have since replaced it but when it started leaking it got water all over the engine compartment well the water had Bars Leak(sealant) and possibly some rust, which has also been taken care of already. Well now I’m just trying to clean up the engine compartment but I can’t get the red rust looking stuff off of the underside of the hood and on some of the plastic and hoses under there as well…

Does anybody know what I can use to remove or clean this up?