I would like to add a Tachometer to my 1980 W123 300D. I would like to use the Instrument cluster Tachometer, but these are extremely rare in West Oz (West Australia).
What items are needed to obtain the signal for the tacho from the engine (sender unit?) and are any other items required to make it work, other than the Sender unit and Inst Panel?

Lastly, would anyone be able to source these for me (metric Speedo please) and send them to me in Oz?

Your assistance is appreciated.

__________________
Tony from West Oz.
Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.