Take an ohm meter, and set it on resistance. Touch one lead to one of the pins, and the other lead to the RCA plugs, each center pin, and each ground shell. When you find the corresponing part of the RCA plug that swings the meter, you have found what the lead is. Do this for all 4 headshell connectors, and you have identified them all.
For example, if you touch the top left pin, and it swings the meter when you touch the left channel center pin on the RCA plug, then you know that pin goes to left hot. etc.
For example, if you touch the top left pin, and it swings the meter when you touch the left channel center pin on the RCA plug, then you know that pin goes to left hot. etc.