Early 4L80e with a later model ECM - how difficult?

[mihela]

That appears to be a 93 model if I'm reading it correctly. If it works with a 91-93 ECM, then it is most likely correct as ONLY the 91-93 model 4L80E had the output reluctor installed in a 4x4 4L80E. Otherwise to be certain you have to drop the pan and look at the force motor to see which one it has.

My 95 4WD trans has the output reluctor.