The #10 steel bulkhead fittings I got from a local shop didn't come with any washers like I've seen in Summit and Jeg's catalogs. I've since been told I'm supposed to have washers between the bulkhead fitting and nut. Question, do I need to use some type of plastic or metal washer? One on each side of the fuel tank wall, inside and out? I did ask the shop and they said they didn't have anything that would fit. Where should I go to find what I need? Thanks.