I have used the CA method.
I don't know if it's just me but the CA leaves a very rough and hard to sand surface, but leaves the fins hard as a rock.
I have found it works best if done before attaching the fins, so you can lay them flat and get a good bite with the sandpaper.
Also, do this in a well ventilated area.
I have also used 3/4 oz. glass but that may be a bit too much for the Duece.