I have a 1986 760 GLE wagon. I began having intermittent problems with the speedometer quiting working then working again. I purchased an instument cluter from a 740 Turbo used( 129K on od. When I was removing the old cluster I broke the circuit boaad that connects the speedometer and temporarliy wired from tha harness to the cluster until the new cluster arrived. The volmeter, gas gauge, temp guage, all worked on the old cluster during this time. When I received the new on and installed it I cannot get the voltmeter to register in a normal range and the temp gauge pins to the right after I get up to running temp. The turn signals make the temp gauge jump. Any Ideas???