I believe the amount you speak of is either line 27 (owed) or 28 (overpayment). If there was a overpayment it seems to me line 3 on the 760C should be line 28 from the 760 for the money you got back. If you owed money on line 27, the number on line 3 of 760C should be 0.
I could be wrong, but it would be nice if an expert could give a 100% definitive answer.
