I used that kind of thing 30 years ago, except mine was a 4 hole version. Mine used something like 6 gaskets.
I only used it for a couple of years. I eventually felt that there was too much of a chance for vacuum leaks since I was learning about carbs and was always removing/reinstalling while trying ideas that were new to me.
Kind of looks like a cool idea, but I learned that I really didn't need it.
Too many cars, too many parts, too little coin, too little space to work in, too little time left to make it all happen!
Update: down to one ride, still too many parts, a little more jingle in the pocket, gaining space, and it's going to happen this year!
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