Unfortunately, Tesla always puts out their manuals tailored to the most current version of the car. It keeps it up to date with the current software that's out there, which is in all cars, but unfortunately for people getting older cars, that means reading about some features you'll never see.
The basics of operating the car, lights, charging, etc are fairly universal across model years, so definitely read through the manual anyway. Just don't get too wrapped around the smaller details.
Some differences you'll want to note between the older cars and the newer cars:
The AP control stalk will have an extra button on the end, not mentioned in the manual because it's not in newer cars. This simply turns off AP.
The manual mentions a spot on the windshield where you can put toll transponders and RFID tags for garages/car washes. I haven't found the real place to put it on my window yet, and the metallic coating on the window does a great job of blocking the signal.
The manual will claim you can open the charge port with the key fob. I don't think older cars do that, or least I haven't successfully done it on mine.
You'll figure out all the quirks over time.