From when I was into the Monte Carlos heavy and the FGMC site, there were two urban legends that could never be proven, one was a LS6 Monte, and the other was a 4 speed Monte LS5. All known Monte LS5 (SS) were autos. There were approx. 600 non SS 402 (396) 4 speeds made. From what I remember anyway.
Kind of like the 70 SS396 L78 auto that no ones ever proven....
(beats dead horse)
Rich