All three sister ships, "Józef Conrad Korzeniowski", "Adam Mickiewicz" and "Generał Fr. Kleeberg" were rebuilt in year 1989.
Removing most of the cargo gear allowed to increase TEU capacity - from 540 to ca. 743. The only derricks kept were:
- over Hold. No.1 - there was only very short hatch, aft of forecastle, letting to small dry cargo room and big cargo tanks;
- over refrigerated Hold No.6. They were still a kind of obstacle, when stowing containers on hatch covers, but there was no other provision crane.

Of course it is a matter of taste, but in my opinion, the ship looked even better after the modification. The original masts appeared too fragile, a bit to weak for the size of the vessel. Much better appearance was achieved in case of "Profesor Mierzejewski" class, of almost similar size.
Also, other forms of reducing cargo gear, like dismounting or cutting them off partially, I find as a kind of aesthetic 'humiliation' ;) like these:

http://www.shipspotting.com/gallery/photo.php?lid=1946807
http://www.shipspotting.com/gallery/photo.php?lid=1513057

In 1991, "Generał Fr. Kleeberg" was providing feeder service from Gdynia to Bremerhaven, passing Kiel Canal every week.

And originally beautiful ship! After removing masts it is much worse, But money is money.
rgds asnyk