sounds like pretty standard wiring for a tacho, so someone on here should be able to help you, (or use the search feature)
black should go to earth, white (should) be for the tacho light = +12v. I would guess that red goes to +12v also and that green goes to the negative coil terminal
Just from memory.. not sure.
see here:
http://www.ausmini.com/forums/viewtopic ... cho+wiring
Matt68 wrote:
"Matthew,
Green wire connects to “S” terminal and to negative side of coil. If there is an aftermarket tacho pick up wire, connect to this wire instead of negative side of coil.
Black wire to “G” terminal and to earth.
Red wire to “I” terminal and to ignition switch.
White wire connects to the thick black wire from lighting globe assembly and then to dash lights.
Regards,
Bob Forrest
Speco Thomas"