Part number for this connection.

[DoingTheBestICan]

I just got a 1984 Mercury 75HP I have a 5 pin connector on the controls box, I have attached a photo of this. . In my research I believe this is to connect a tachometer, if I am not correct please let me know. What is the correct part number for this connector or cable? Can I use any tachometer for this or is it for a specific one. Thank you for your help.