[V8] Motronic part numbers

[Peter Littlewood]

Hi Folks
Well the sluggish, smokey, misfiring v8 saga continues!
 After changing plugs HT leads caps rotors, Lambda sensor FPR valve, coolant sensor on clylinder head and checking wiring and testing pin out etc... I can only now assume the ECU is at fault.
Can someone please help me with the part numbers? Bosch number I have is 0 261 200 198 with the audi one being 441 907 404 H.
I am struggling to find the correct one. Ive seen several with the same part number but a different Audi number.
Does this really matter? I really want the correct one because I'm fed up of chasing my tail and burning cash !!

Many thanks

Pete Littlewood
1990 V8 auto UK spec