ZF 4HP22 Gearbox as used in some Porsche's -I Need a GCU

[Espritment]

I purchased an unfinished Cobra project which has a BMW V12 engine with a BMW Auto gearbox, which I believe is a ZF 4HP22 gearbox. Getting the engine to work without the donor car ECU and wiring does not seem to present a problem, but getting the Gearbox to work is proving to be difficult.

Can anyone suggest a possible solution. Thank you.