Are they flat?
Is that razor thin common wall flush with the rest?
If so, run them. Take and gasket match the intake and go for it.
If it's not flush and its open.. how much ?
Enough to disrupt or cause distribution issues?like a stove bolt or whatever the hell siamese port pos it was.
They came off of running engine. I happened to ruin a nice factory manifold too. LOL. I recently tore the engine down and was surprised to find the trimmed intake gaskets intact. It ran pretty good. I think the porting didn't help or hurt.
