Early 1970's had no wording on the lens. Then it changed to "shift gate". Then finally, it went to "slap stick". When did they go back to the ball? Was it right at the start of the model year or was it a running change? Did some very late 73's get the ball handle OR did some 74's get the "T" handle?
The "T" handle at the beginning of 71 was different then the later versions. The base of the handle(and the plastic shift plate) were a different shape.
The original "T" handle on my 73 broke. My dad made a round knob out of wood to replace it. He used that wooden handle for a couple years before a friend of his found another "T" handle in a junk yard. I think that wooden knob is around here somewhere.