Sorry about that -a typo -,I should know better than to try and multi-task
This particular manifold does not have steel tubing to pass coolant,(used for
heating the manifold)I gather Edmunds made quite a few versions.Others have steel tubing cast in the aluminum manifold.I based my response on the experience of having worked in a shipyard for 10 years and seeing what happens when brass and aluminum come in contact.I've seen aluminum reduced to a powdery residue.A more correct term may be galvanic action.
It doesn't take much moisture to get things happening.I don't claim to be an
expert,but as a rule of thumb, I would not assemble anything placing aluminum
and brass in direct contact.In a dry climate maybe not so much of a concern:)