On the spacer shown where the pcv fitting is you see the back of the spacer has "hump" built into it. It's open underneath the spacer and has to seal to the manifold. On the OE manifold its machined to fit a spacer like that. If the Edelbrock has the same machining it will work. I tried that spacer on a yblock manifold (without that machining) and ended up with a giant vacuum leak. Hope that make sense.
