hey mike, sorry for the confusion.  assume i have the following:

1) static xml
<items>
  <item id="1" type="clothes"/>
  <item id="2" type="cars"/>
  <item id="3" type="tvs"/>
</items>

** this should be easy

2) i need to derive a unique set from the following:
<new-items>
  <new-item type="house"/>
  <new-item type="boats"/>
</new-items>

<new-items>
  <new-item type="windows"/>
  <new-item type="boats"/>
</new-items>

** i can use muenchian to get uniques

2b) i need to combine (1) with (2) to get:
<items>
  <item id="1" type="clothes"/>
  <item id="2" type="cars"/>
  <item id="3" type="tvs"/>
  <item id="4" type="house"/>
  <item id="5" type="boats"/>
  <item id="6" type="windows"/>
</items>

*** i'm unsure how to do this and in particular concat the 2 maps and
gen the sequential id's for house, boats, and windows.

3) finally, for some set of items
<items2>
  <item2 type="house"/>
  <item2 type="boats"/>
<items2>

i need to x-ref it to my 2b list and produce:

<items2>
  <item2 type="house" id="4"/>
  <item2 type="boats" id="5"/>
</items2>

hope that's more clear.

thanks.