Changing Line Item Formula to Refer to List Subset Instead of List.Property

Hi all... I'm a modeling newbie hoping an experienced Anaplaner can spot my mistake here pretty quickly. I inherited a model containing Module XYZ that contains a line item with the following formula: 'Module ABC'.Amount[LOOKUP: Account_List.Account_Property_X, LOOKUP: Subsidiary_List.Subsidiary_Property_X] Both list properties are list formatted and contain values identical to the list items to which they correspond (e.g. if 12345 - Deferred Rent is a list item in the list Account_List, the value for Account_Property_X is also 12345 - Deferred Rent, and that value is pulled from a separate, mostly duplicative list called Other_Account_List). I have adjusted the model so that now Module ABC applies to Account_List, and Module XYZ applies to Account_Subset, which is a subset of Account_List.  I've eliminated the duplicitous account list and the Account_Property_X, which merely repeated the list items, and I've made the same adjustments to the subsidiary lists. I can't, however, figure out how to replicate the result of the formula shown above by just referring to the subset list, instead of list.property.  Anyone have any pointers on how to write an equivalent formula in the new environment I've created?  Or are my attemps to "clean up" the strucure in this case misguided? I'm happy to provide more details if I haven't provided enough useful information. Thanks! - Chris