Soooooo I have continued the dodgy day all by myself
Did a bit of googling and found a guy on the UK forum who had the exact same problem, car fires and runs for about 2-3 seconds then it dies. He tracked it down to a faulty ignition module. Had a bit of a look at the Fatty mobile and found a mess of wiring where someone has tapped into the loom presumably to fit a module to kill the ignition if someone pinches your car. Moved a few wires and found this.

After removing a couple of kilos of solder from the wires and the scotch lock I've soldered it all back together and put some heatshrink over the wiring.

Fire the car up and it runs for about 30 seconds and then dies

Call Fatty and he tells me what wires to play with so we can bypass his aftermarket DFA, did that and it RUNS!!!!!!!!
Changed the fuel filter while I was at it and noticed the there was no bracket to hold the filter in place. Cut up some alloy and made a bracket with two cable ties to hold the filter in.
