Originally Posted by Matt Monson
That's not what he's saying. The Ej257 will work, but you just want to use the Ej25D (dohc NA engine from 1996-1999) gasket. It's a phase I gasket and is thicker, which is what you want since you are using phase I heads. It's both the right compression ratio and the right manifold spacing. You just need the gasket, not the block.
I have used the 257 HG on a EJ257/EJ25D build, intake manifold fit/lined up fine.