The base V8 engine (327/210) would have come standard with the 10 bolt 3.08 ratio with either the 3 speed manual or the 4 speed manual. The 2.73 was the optional "economy" ratio while the 3.55 was the optional "Performance" ratio. The stamping for the 3.08 would be "PA" and the date would be a day or so, to a few weeks prior to the cars build date.
The speedometer cable part number would have been P/N 6477132 (or P/N 3878814) for the base 3 speed, and P/N 6454863 (lower) and P/N 6477129 (upper) for the 4 speed. (The Saginaw 4 speed used a 2 piece cable.)