Update: I've driven the firetruck over two hundred miles in the last two weeks "without" the cardboard fix and there was not a drop of oil leaking on my valve cover. I don't know what fixed this issue for my rig but I like it even better now. LOL
And I've checked the oil level in the engine and its full. So I don't know what strange thing will happen next... The truck ran didn't leak and never went over 180 degrees. I'd recommend the water pump mod to anyone who has the overheating truck issue.
