I got a set of casting 3462346 heads which should be the 70-72 open chambers, and they have dual springs and aluminum retainers. Must be aftermarket of some sort?
I have 2 383s, one is a seized '69 2 barrel and the other is a '67 magnum 4 barrel with a blue crank. Can I use the '69 2 barrel crank (working on getting it un-seized) in the '67 magnum block?