This type of nuts were used on all of the outside-plug 250s from the time of the introduction of the GTEs through the last of the 250 Lussos. The 275 series cars changed to the flat, round, knurled nuts. Three-ear air cleaner nuts.
On the 250 series P.F. cars, such as the Coupes, Cabriolets and the GTEs, the electrical panels are mounted in the engine compartment and are protected from the elements by a black wrinkle-finished aluminum panel. These covers are held in place with three small knobs. These knobs are machined from brass bar stock and nicely finished in chrome. 250 P.F. Electrical Panel Knobs
Red fiber washers were used to seal the mating surfaces of the components on the fuel log and carburetors. These are all 12mm I.D.. Copper washers were also supplied with the Weber carburetor rebuild kits. Weber also supplied brass, unplated nuts, banjo bolts and other pieces as replacements. It is my opinion that the cars were delievered with the red fiber washers and with all of the fuel log components chrome-plated. 12-Piece Red Fiber Washers for Outside Plug Engines