1-What do the numbers displayed across the top and left margin of the flood maps represent?
2-Inside each block on the map there is a number (located in the center) it may be 5 or 9 or 35 or... What does this number mean? Wondering if it has anything to do with section, township, or range.

Can you provide the Community Number and Panel Number of one of the flood maps that you are inquiring about? I would be happy to help you interpret the features that you are asking about.

I am taking a guess at the first question, and say that they are used for matching up two maps. You will notice that in each margin it will state what map lines up to that edge. The second number in the center of each square is the Section #, the township and range # are marked on broken lines across the maps and are labeled with T or R. Hope this helps.