I went to the machine shop today and I was told that to take 1/16 inch off three of the four mounting surfaces to make it flat would take hours and likely cost me way more than a new manifold. The guy said that is so much material to remove that it would take hours because they'd have to keep waiting for it to cool. I'm just curious to know what those of you with shop experience have to say about this.
What he recommended was that I use what he called orange RTV, which he swore by. He is sure that will take care of the difference. I have to say I was surprised. I looked up orange RTV and it seems it is Permatex Ultra Copper. I'm going to give it a try over the holiday and see what happens. I read the technical data sheet for it and it is supposed to be used for this application, so I'm hopeful it will work.