In many people's opinion they would not "require" any modifications. The lume is good on the dial and hands, the canon pin is flush and the dials are generally very good. All of these things would take more money than the difference between his watches and those offered by others, and take much more time.
If I had to start all over again, I would make my first purchase a 177H from DSN. Then that might be the only watch I would need.