Partial delinking of linked charts

[#1]

I am looking to set up some linked charts as follows

Chart one showing sales value by SKU for  a selected period of time (say last 3 mths) the SKUs would be ranked from largest to smallest sales

Chart two shows Inventory by month linked to chart one.

I can then select an individual SKU within chart 1 and see its inventory profile in chart 2

However what I want to do is have a different time range in chart 2 so I would like to be able to use a user selectable date range (say 90 days) to select the SKU's to analyse but then when I select that SKU it blows out the inventory by month for a separate user definable date range say 360 days

I would like to maintain all other filters as linked for simplification for the end user

Thanks in advance

[#2]

A chart to perhaps demonstrate better