Post on the bottom, this allows the reader to read or review the quoted material to get the idea of what your response is going to be concerned with. But keep in mind the reader will have to scroll though the whole quote. If its to long then the reader will skip it, be annoyed with and less sympathetic for you, or completely ignore the message. Which doesn't bold well for you, as your intent was to provide some information for other readers. So presentation helps in writing to your audience.
