The CP is a _very_ simple one:

The spinner and knob should be available. The P1 and P2 buttons are no-brainers because the typical "german cab" buttons and should be available for sure.
Not sure about the joystick/handle...it wouldn't hurt to use a US one IMHO.
Too bad this is converted....I'd love it......it is such an underrated game....and one that needs the original controls all the way.....
Is yours already working again Ully ?