Did something similar with the power steering cap on my Camaro. Set it on top of the air cleaner with the pointed side up. Ruined an otherwise good hood.Awesome! Better a paper towel than some hard to chase down issue! Even being as careful as I can every now and then I do some silly thing. One time I folded my hood because I had left a roll of tape on top and slammed the hood thinking the latch was just sticky. Even checked for obstructions and just didn't see it.
I had pulled the pump and cleaned that tank out before I even pulled the truck off the trailer. It was literally the first thing I did to the truck.
My wife is a nurse and all she could say was ‘you should have counted your sponges’ in her typical smart alecky way.