Could someone please tell me what each sectioned number of a Yamaha part number means.

For example : A front wheel might have a part number of:

4H7-25168-29-98
(1st 2nd 3rd 4th)

I think:
1st # - maybe specific to the bike's model. (In this example it's a XJ650RJ)
2nd # - maybe specific for the part itself. (In this example the front wheel)

If my guess is wrong for the first two numbers, please let me know.
What are the 3rd and 4th numbers for?
Even if you do not know what the numbers are for specifically, maybe you can tell me whether or not the last 2 pairs of numbers are important when interchanging parts between different XJ models.
It makes me so mad when I find the perfect rare part and the difference between the part numbers is the difference of 00 & 01. Thanks. B)