Outer Limits 4x4 Board

Howdy, just trying to replace original diesel tacho (broken) with a VDO diesel tacho and have a basic wiring question...
My original MK patrol diesel Tacho has 4 wires as follows
BLACK
YELLOW/BLACK
YELLOW/WHITE
YELLOW/RED
My VDO diesel Tacho has 4 wires as follows..
RED
BROWN
LIGHT GREEN
GREY/RED

My question is easy.. WHAT JOINS TO WHAT???? I can solder but my psychic abilities are a bit rusty.. and someone stole my multimeter..lol

ok i dont have a clue how to read wiring diagrams but

black earth
yellow black to ignition coil
yellow red relay ??
yellow white NFI ( LIGHTS PERHAPS )