Need advice on splitting xml data

Hi, I have an xml file which I need split into two files due to a change in our implementation for a newer version.

Basically I've got something like this:
<store>
<inventory>
<item name="a" price="1" stock="9"/>
<item name="b" price="2" stock="8"/>
<item name="c" price="1" stock="7"/>
</inventory>
<inventory>
<item name="d" price="3" stock="6"/>
<item name="e" price="5" stock="0"/>
</inventory>
</store>

and using xslt I want to split it into two files like this:
File A:
<store>
<item id="1" stock="9"/>
<item id="2" stock="8"/>
<item id="3" stock="7"/>
<item id="4" stock="6"/>
<item id="5" stock="0"/>
</store>

File B:
<items>
<item id="1" name="a" price="1"/>
<item id="2" name="b" price="2"/>
<item id="3" name="c" price="1"/>
<item id="4" name="d" price="3"/>
<item id="5" name="e" price="5"/>
</items>

Should I generate one of the files first and then generate the 2nd file by getting the 1st as an external document? Seems like a little bit of a hassle; I'd like to find a simpler way if possible. Also, is there any easy way to get a random unique id #?

Thanks

Joseph

ah, never mind was making this problem a lot more complicated than it had to be. Friend gave me a solution to create a secondary xml file:
<inventory>
<item name="a" price="1" stock="9"/>
<item name="b" price="2" stock="8"/>
<item name="c" price="1" stock="7"/>
<item name="d" price="3" stock="6"/>
<item name="e" price="5" stock="0"/>
</inventory>
and use the position function to create the other 2 with linked ids. thanks anyways