Not sure if this is helpful re the later D1's? See below.
It is from the lr4x4 link in this thread
Loanrangie did you try this?


I just spent 3 days looking for a little black box called the spider. I have a 1998 Discovery 1 and had the problems you described. Won't start, let sit starts ect. I tore out my dash in 3 degree weather because it finally became a 5000 pound paper weight and would not start at all. You can imagine by displeasure when I finally got the center dash free and there was no little black box. After many quires and hours looking at land rover circuit drawings I finally found out that in 1997 or 1998 land rover built the engine immobilizer circuit into the alarm module Z163 and used a transistor instead of a relay. It is behind the dash trim under the glove box. It has 2 connectors C225 and C274. If you solder a jumper between pins 10 and 11 the truck will start. Please let people know that at least 1998 up does not have a spider relay deap in the dash.
Thanks for the info though it got me started down the right path, just didn't need to take the side trip through the dash.