Something to keep in mind when comparing Coyotes to other critters is the physical size of Ford's OHC V8s...much larger in width and height than the SBC. Weighs more, too.
So now you run into packaging issues. More boiler room required. Cowl height and frontal area issues. And don't forget a Lincoln 4-dr is supposed to share the next-Gen Stang chassis, too. If so, Lincoln will have input as to body-chassis structure and specs, just as Cadillac has with the Alpha derivatives.
There's an opportunity for GM to create a Gen-6 Camaro that, for once in a long-long time, is the same size or even smaller/lighter than the next-Gen Stang...and the physical size of the SBC plays a part in that overall physicality.