That plate that allows all the plugs of the motherboard to stick through should just pop right out. If you push on the long side of the plate closest to the motherboard from the outside of the computer, then it should fairly easily come out. Though if the motherboard is still in the case then the plate probably won't pop out very easily.
Then you can take that plate and put it in any other case.
Though, if your computer is manufactured by like Dell or some company, I don't know if they have plates like that in their cases, but I would bet they do.
db
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