Can you help me to start a 318 TDS

Hi, I purchased a 1995 BMW 318TDS with the expectation of removing the engine and gearbox and shoehorning it into a 1948 Triumph Roadster.  (More power, more MPG).  The previous owner explained to me that the car’s electrics would not recognise the key, and that the BMW agent wanted £1500-£2000 to rectify the fault. 

1)      Is there any way that I can by pass the key recognition system?

I have tried, disconnecting the fuel pump cut off solenoid and energising the pump separately, and I get fuel to the pump, but nothing to the igniters.  Therefore, the car would not start.

2)      There is another loom going to the pump which goes to a 4/5/6 pin plug on the bulkhead/firewall.  What does this do?

3)      Is the fuel pump protected by the alarm system?

4)      Is it possible to do what I am trying, or am I being too ambitious?

5)      If I went to car breakers and bought a matching key and recognition unit, proving the replacement was OK, would this work if I installed it in my Triumph?  What does the recognition unit look like and where is it fitted in the car?

6)      If I can get the car to run, should I transfer the BMW loom to the Triumph?

All information, no mater how small, will be of great use to me.

Many Thanks

Paul S