I just finished a cap kit change for my Duck Scan.
I found the main cap 220uf 400V that was worn and expanding, replaced that. The picture was very slow to appear and its much better now.
I also found that it didnt really do much else for the quality of the image or the colours.
thanks private gump. I may as well change all the electrolytic caps since I have it out. I will post a list of component numbers and values when I am done.