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Motion Valve covers are by far much more common than the Yenko covers
Dan
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Not at my house they aren't.
I have a closet full of NOS chrome plated ones in sealed boxes. The bad thing about these is they won't fit a Camaro or Nova with power brakes unless you severely modify them. If they are the plain stamped steel variety (non-chromed) I would say an even swap for a pair of real finned aluminum Motion covers would be more than fair.
