Manipulating Tree Prompt Values with Caption???

[torre2011]

I am building a report from a cube, and within one dimension there is a level that is displaying duplicating member captions but with different MUN's....kinda like this:

Premise Type
(Members)
-----Non Retail
-----Off Premise
-----On Premise
-----Non Retail
-----Off Premise
-----On Premise
-----Non Retail
-----Off Premise
-----On Premise

The reason for these duplicates is the alternate paths used within Transformer, to allow for two disparate dimensions to be used together.  So in reality it should look like this:

Premise Type
(Members)
-----Non Retail - Central
-----Off Premise - Central
-----On Premise - Central
-----Non Retail - East
-----Off Premise - East
-----On Premise - East
-----Non Retail - West
-----Off Premise - West
-----On Premise - West

So with that out there...i am trying to find a way to manipulate the tree prompt so that it only shows a distinct set of members, and when the user selects one, we filter the report on all member captions that match it.

The tricky part i think besides what I just stated, is that there already is a filter for the Business Unit ( Central, East, West)...so if a user selects East, then we should only show them the distinct values within the tree prompt for just that Business Unit

I just thought I would get this out there...and see if anyone bites  ;D

Thanks!