Well the rev counter has behaved itself after being operated on, it was not easy as there was only .5 mm between soldered pins, so had to use a powerful glass after to make sure I had not bridged any, as for the glow plugs that is a different mater, seems there is a sort of ECU that controls the plug relays and the EGR stuff, but this is the interesting point, the plug configuration on mine is according to the diagram for Switzerland and West Germany, the one for the UK is nothing like mine, so sorted out the relays and disabled the earth connection and connected the 2nd cable direct to the plugs, but it cut after initial start as the control unit expected to see half voltage when the second relay kicked in so went into disabled mode, I now have to find the wire that connects direct to the plugs and cut it then put my own relay in that fires up when the second relay comes on and feed half voltage to the control unit, trouble is I am not sure what resistor to use because this will depend on the load, in other words it will not just be a resistor but a small circuit that reads half of whatever the voltage is at that time as I am sure there will be a comparator built in, pesky control boards, wish Ray was about, Rick