If you just grab everything on a single line template, then create a summary, and simply select "suppress duplicate values" on the display tab for at least one key column, say Acct#.
Then export this summary as a fixed width text file and open the export as a report in Monarch. You'll then be able to trap so as to distinguish between the first line of data and the subsequent lines for each Accnt#.
(Sorry, I realise that was a bit rushed, as explanations go...) On the second pass, trap just the first line, and for the final field, set the advanced field properties to end on "none of the above". This will let you see the data as you want it in the table.