The very early 175 crankshafts are different. Later 175 and all 200 crankshafts are the same. The later crankshafts had a center bearing with a location hole and two lube holes in the outer race that weren't in the original. The later crankshaft will fit early engines, the early crankshaft won't fit the later engines (it will, but you have to remove the locator pin from the crankcase).