OK, if you look up above it's clearly a '71 or '72 tach, the number is 230/41/10. I can't really read the number from your second photo but I am pretty sure it's a 72 date code.
You can confirm by telling me what the white plastic terminals say. If one of them is "C" then you have a later tach designed to be driven directly off the points. The earlier tachs have a pin labeled /1.
Here is the factory wiring diagram for the CDI ignition, very simple.
