My rearset just arrived. My assumption was that the rear peg fit into the collar that attaches to the z-plate. But it doesn’t, the peg is too big. I can only think of two options. 1) grind down the peg some until it fits. Doesn’t sound right. 2) there are special pegs that are designed for the rear set and I need to find one. Anyone have an idea which one it is?