Another Carb question

[John in Ct]

I am working on my IH 154 carb ( see a previous post from a couple of days ago). In case that doesn't work out I want to have a backup plan. A few years ago I got an NOS IH carb # 364 579 R91 ( which I think will work with my 154) and I have a few qusetions on if I have to use it. It is dusty from all of the years and needs to be cleaned. Should I disasemble it, soak it in a carb cleaner dip like a regular used carb? I really didn't want to scrape the gaskets off which I am sure are stuck on it. It also has a little corrosion near the gasket.
Also, a 154 carb uses a different choke shaft so should I use my good 154 bottom? If I were to use my 154 bottom, what else should I swap to use with my NOS top? I could use the NOS bottom too ( with my 154 choke shaft) but where the choke shaft comes out of the NOS carb ( splined end) there is a plug on a 154 carb instead of the second dust shield. That plug is no longer available, would anyone know where I could get a plug?
Again I would rather use my existing carb but I need a backup plan . Any thoughts, ideas? Thanks!!

[Don McCombs]

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[George Willer]

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