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At 5'6" you're 170cm tall, a large FD jacket and pants when laid one on top of the other measure 180cm long, and the XL measure 203cm long. At 5'6" I would go for the large and then use suspenders, get the suspenders working well and your L pants will look XXL.
There's also a zipper at the bottom of the legs so you can open them up a bit more, at least there is on the v3