The NV4500 is the same for all years.
4500 and 5600 1st gear is the same, 4500's 4th is the 5600's 5th, 4500's 5th is the 5600's 6th.
5600's 2nd is slightly lower then the 4500's...
5600's 3rd is higher then the 4500's 2nd and finally...
5600's 4th is slightly higher then the 4500's 3rd.
I think I got that all right.
Now that I went back and read your post again, I see that you couldn't care less about the NV5600, I'm not very smart sometimes.
All NV4500's are created equal. :-laf
-R. J.