I just took my 2.4L plate over to my merc graveyard where the 2.5L leg lives to be 100% sure that my memory was correct.
Looks like there's one more step if you want to use the 2.4L plates.
Or you could stay just use the top 2.5L plate which would be a lot less work . . . but you have to go back to the store to get right gasket.