This is doable.
>
> Save as FileName_RedOnly
>
> Ctrl + H to get the replace dialog
> Set up as follows:
>     More >> Format >> Font >> Font Color >> Black
>     Use Wildcards
>     Find what: *
>
>     Replace with: [blank]
>
>
> Now, press Replace All.
>
> Done


Ryan, thanks a lot... It does work as you said!
I was already on the right track but didn't use Wildcard and *.
BTW, selecting the color can also become a problem since one can easily
select the wrong one (there are several of dark squares which look very
similar).

Sigi