would it be possible to run 4 batteries in series for a total of 48v and then run that in parallel with two batteries in series (24v) for a final voltage of 16v?
This is not a stupid question..... Its actually a retarded question. HA HA... Just kidding.
To answer your question in the simplest terms.... No it will not work. The series connections that you calculated is correct but by connecting both series in parallel would drain one set of batts and prolly overcharge the others. Remember that you are dealing with a difference in potential (voltage) and could really be dangerous.