Need Help!!!!

I removed the Banks Monster Exhaust from my truck today and put the stock system back on, but I don't have the two nuts that hold the counter balance weight to the stock exhaust. Does anyone know the size and thread count of these nuts? I'm pretty sure they are metric, but that's about all I know. Any help would be greatly appreciated!

I think this summer I'm going to look into finding a custome exhaust place that can fabricate a new 2.5" system from the point it bolts to the headers to right before the stock muffler, and have them make it with a free flowing "Y"! Hopefully this will enhance performance a bit without sacrificing low end torque. But until then, it's back to stock! Anyone want a used Banks system, let me know! The details are listed in the Buy/Sell section.