Thinking about 20a) Sort of tank that's seen above column (6) ?E?D?R. I have either FEEDER or TENDER in mind, but I do not the importance of the column bit, and I am sure that is the key to the clue. Any thoughts?
Adding another question to an existing thread sometimes get missed as other, newer threads jump to the top of the page. You can always start a new thread if you do not get quick responses.