RH - 398704 - 330 - 350 Standard issue manifold.
LH - 380001 - 350 X-over manifold

I've been asked this question. I'm not sure the answer. I do know that both the 350 & 403 are both considered to be small blocks. Still not sure if the above manifolds will work. Any help would be appreciated. Thanks

 

Yes, externally all 307, 330, 350, and 403 engines are the same. The 350 manifolds will work fine.

 

Thanks captjim. I appreciate your help.