I think you can bolt up any head to the Vortec block but don't quote me on that. Only the bolt pattern on the vortec intake side (where the intake bolts to the heads) is different. So if you can used the old style heads on the vortec block the old style intake will work. The block its self should be just like a standard 1pc rear main seal 350 I would think.

I haven't researched the vortec block myself so don't quote me but I believe that's how it should work. Maybe somebody else can chime in.