I have a bseries with a hydro tranny in my 87 teg. I can use the standard electronic speed senor mounted in the tranny, but then i have no speedo. My other option is to mount the old cable sender from the d-series tranny into the hydro tranny. This allows the speedo to work, but I'm not sure where i need to tap into for the propper vss signal to the ecu. I suspect that it's the cruise control speed sensor signal that i need to also send to the ecu on OBD0 pin B16. I tried the standard PGMFI signal from the cluster with is listed at 4-5V at 10 mph. The cruise control speed pulser generates 4 pusles per 1 cable revolution. I have been unable to determine what the OBD1 ecu is looking for on pin B10. Any help would be greatly appreciated so I can get rid of the VSS error when using the cable driven speedo.