Alfa 75: are 3 litre V6 crankshafts all the same?

[ACE]

The late model 75 3l V6 uses a Motronic ECU and a crank angle sensor integrated with the pulley mounted on the front of the crankshaft - the toothed wheel.
The earlier 3l V6 (with Jetronic ECU) does not have the same pulley arrangement.

Question:
are the crankshafts from these motors identical?
I.e. are the pulley assemblies interchangeable or conversely are the crankshafts interchangeable?

Cheers, ACE