It sounds like you went with a packaged stroker kit.

Are you sure those rods are not stroker clearanced all ready??.

Many people want to turn back the clock and use the older heads.That's fine,but understand how much your giving up over the many good deals of aftermarket heads.Pat listed a whaling deal on SPH 180cc heads this week for only $600.And he has the shop with tons of experience to fill them out to make a real ba$$ torquer 383 along with the tech support you would get from him in parts selections.Look in the parts for sale section.Might want to PM him.
Ya know there is certainly good reasons why yrs ago the aftermarket head business came into being.In short it was to see how limited stock heads are.