I'm not sure, if you are processing on the .Net side, I would look for all the occurrance after the last one use a lastIndexOf.
In CR, I'm not sure if they have such a function. You could probably split the line into an array, search from the end to the beginning of the array and replace the offending array values with "", then use the JOIN function to get the string back. I would probably check for double spaces and replace those with a single space.
It may not be optimal, but hopefully it will point you in a direction to a solution.