HI Warren,
You may be able to interface to the PCM via SCP then feed signals to the dash if it doesn't hook up to the SCP protocol?

I notice you say SCP was on pin 15 and pin 15. A typo?

Is yours a 60 pin EEC-V ?

I am trying to wire one of these up on the bench (catch code CHCA)

My ECU is from a Ford Fiesta mark 5 Zetec (same as Puma?) I have EEC-V on the label, with a 60 pin connector (3 rows x 20 pins)

I have tried pin 2 of OBD to pin 18 of ECU and pin 10 of OBD to pin 19 of ECU, with 12 V to ECU pins 1,5 and ground (0v) to ECU pins 20,16, 37,57, 26,40, but I cannot initialise the ECU with SCP / J1850 PWM protocol.