Glad it all worked in the end JohnMat. I assume your car is a more recent one? I think there may have been a few changes to the wire loom about the time of the Euro 4 spec cars introduction, early 2018. Possibly the black/grey and black wires plug was deleted as it seems to be very elusive on later cars. Your fix and splicing into the black/grey cable at the speedo achieves the same result. You may need a little adjustment after a check run but it will be a lot closer than when set at 3295, although your 0-60 time won't be so impressive now!
