Looking up text values in a col. and replace text in another col

Hello, I am trying to lookup a partial text value in column 1(e.g. lookup all cells with the suffix AAL in cells that have an actual text of say AAL687). For those cells that match I want to change the value in another non adjacent column (say column 6) to the text value "R". The values in column 1 are NOT ascending.

Any solutions?