Elvis' harmony vocal overdub on 'Bridge Over Troubled
Water' is not present as heard on FTD's Taking Care Of Business - In A Flash, but it is present on the bootlegs You Know, It Don't Have To Be Strictly Country Volume 2, Pure Diamonds Volume 2 and For The Good Times and all of these releases contain brass and strings overdubbed after Elvis harmony vocal overdub. This was achieved by either turning on or off the separate "Harmony Vocal" track on the 16-track tape.
Sample of 'Bridge Over Troubled Water' with Elvis' original vocals in the left channel and his re-recorded vocals in the right channel.