What is the proper wing nut to use for an original air cleaner. Is there a flat washer associated with the wing nut? Pages 330, 331, and so on show a wing nut but it is difficult to see clearly. Paragon shows item 615 as 'Forged Type' Chrome. I would love to see a photo of what is felt to be an original, the dimensions and finish. Mike perhaps from the Almond car??