Just picked up a cheap f150 for one of my kids first vehicle. Previous owner thought the gem module was bad, and the owner before him had pulled the wiper arms off the front and threw them in the backseat, but they lost the nuts for the wiper arms. For the life of me, I can't find replacements online, and I don't know what the size of them would be....anyone have any idea what size and thread they might be off the top of their head?