Hi 1930.
I am familiar with the article, but thank you for posting the link anyway, it is always useful to read it again. I read all the articles many years ago, and I recommend others to do the same, they provide very valuable info.

There are many threads in the forum discussing manifold machining problems. In some cases the distortion caused be heat has been so severe, that a definite answer to a question on how to attack the problem will be difficult to make. There is another thread running now, Super Six Dutra dual install with pics, where you can see the problem of cracking because the two manifolds were not aligned. Even if I would suggest that the intake and exhaust manifold were bolted together before machining, as described in the article you refer to, it depends on for example if the manifolds were previously mounted together, or if they have different origins. In many cases, an intake and exhaust manifold picked at random and bolted together, will have ports that do not line up with the cylinder head at all, and in those cases, the manifold joint flanges may have to be corrected first, any other machining may just make things worse.
That is why I hope that some members with practical experience from a mechanical workshop, and who have worked on several manifold machining problems, will make some comments on the matter.

Olaf