Splitting merged mass addition lines.

I have a tricky scenario that I need help in finding a solutino for.  In Oracle Fixed Assets, I know that we can Split mass additions that have been Merged.  However, the business frequently gets Invoice Price Variance (IPV) mass addition lines transferred to mass additions (Negative value) that when combined with the item line, makes up the actual value of the mass addition.  For these mass additions, they typically also want to split this item line into several assets.  To do that, I've instructed them to change the Units in mass additions to the desired # of assets and perform