[skidlids]

I would be more worried about the lack of info from the Air temp and Air pressure sensors as that info is fed down the CAN line to the ECU while the revs travel up the CAN to the dash
But I bet some settings could be entered that it runs OK most of the time without trimming the fueling by way of the varying air temp and pressure

On a 916 I recently sold I had a Elliot revcounter fitted in place of the stock tacho and that picked up off the coil trigger wire.