I've can't seem to find a clear answer on these little dowels that line up the cylinders. I have six after disassembling the engine. My question is, do any of these dowels need an o-ring to properly reassemble the engine on a 1972 CB350? This is my first post, but i've spent countless hours reading thru this forum and finding answers to any question I might have. So thank you all for taking the time to share your knowledge!