The 2V always had fabricated extractors from the factory. Never a cast manifold. The precrossflow 250's cast manifold won't fit properly as it's open at the top of the 3&4 exhaust ports. You can clag it up with weld - but why would you?
Every set of extractors I've seen will fit the 2V and regular head, so no need for worrying about differences there.
Cheers, Adam.