I was cleaning my carburetors and I removed the air mixture needles. I noticed at reassembly that one of the "O" rings had been left out. So I took them each out to find out which one was missing the ring. That's when I noticed something really odd. There is a metal washer and an "O" ring on each needle. Seams to me that the metal washer should go between the spring and the "O" ring. (To protect the ring if the spring rotates.) However, looking at the exploded parts breakdown, it seams that the correct order is to put the spring on the needle, then the "O" ring then the tiny metal washer...insert and screw it down. I wish I had paid attention when I took it apart but I would swear that the "O" ring was on the outside. Can anyone verify the correct order for me? I am waiting on new "T" fittings and bowl gaskets to come in, so I have a few days. Please don't guess. If you have a benched carb for reference please check it out. I attached a portion of the exploded view I found online. I couldn't get it centered but the needle assembly is at the very bottom.