Why not use outlander inverter with motor? Easier to work with charger as well. Also heater and ac compressor.
@celeron55 my pug 406c has mechanical speedo as well.
@youngpoland
I bet your car uses the same Xantia BSM as mine or very similar...
I made alternative signal converter on RH driveshaft which tells rpm to arduino and it converts this to speedo talk. Now that would not be neccessary with outlander inverter which reports motor rpm on CAN. Then VCU converts it to correct pulse train for dash.
RPM dial could be run in this way as well, only i suggest to display current information there instead.
See a BSM file so you can fake its analog signals

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