340 Exhaust Manifolds on Edelbrock Heads

Back in 2000 when I put together a 340 with Edelbrocks & manifolds I uses spacers, then the next year I was at Spring Fling & wound up speaking with Steve Duilich and he mentioned he had ground the raised area down and wound up hitting the water jacket.... I would suggest using spacers, or at least be damn careful about how much you remove...