SB Exhaust Manifold Washer Question...

Are the Conical Washers used on Every Fastener?
I have 8 of them, they were used on the Outside Studs and the Center (Dual Part)
but had regular flat washers on the Fat part of the Manifold. (with the longer bolts)
Should I Use 4 more so I have them all the way across? Or are the Flat ones okay?


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