1985? Mariner 50hp 4 cyl 2 sroke

[bleybl]

Hi,

I am a new member from Auckland NZ.

The question I have is, can anyone tell me how to connect the electric rev counter to my recently purchased 50hp 4 cyl Mariner o/b. Also, I would love to know what year it is. No. 5869789 made in Wisconsin.
Many thanks, bleybl.