FF30 TACHOMETER

Hello to everyone, I am currently restoring a TEF20 and want to fit a tachometer to my tractor ( the same as the one fitted on a FF30, i have the gear fitted on the end of the fuel pump and the plate to accept the cable but am unable to find a cable at present, can anyone please suggest a supplier? can you also tell me or post a picture of the gauge used and the ratio of the gauge, i would be most gratefull if you can help me in my quest, i will try and post some pictures of my restoration and of the various parts made during the restoration. Regards John.