Get the 235 manifolds. The ports are bigger. You will also need to get the carb with them, mounting holes are different. Alignment rings are a must, too. They are bigger for the 235.
When I install the manifold gasket set, I use some ultra-copper sealant on the manifold side of the gaskets. Allow the sealant to cure for 24 hours before running the engine. This will usually eliminate any intake and exhaust leaks.
