CPS differences?

Just out of curiosity..how do the CPS differ? Are they broken down to engine management systems? Renix,OBDI,OBDII?

I'v never considered grabbing one from a u-pull but with a bud recently having one fail, my rig sitting in driveway with a suspect CPS and the fact that 3 94 Jeeps w/4.0L will be heading west in Sept i'm considering grabbing a few as possible spares.

They definitely differ between the Renix and Chrysler types. Their electrical characteristics are different, though I'm not sure exactly how they differ in function. I think also that the 91 is different, perhaps just in the wiring connector. But I'd avoid that one too. 92 to 95 would be guaranteed compatible. I think there's another connector change in 96 and up.

Your correct on the connector change in 96, just checked a spare engine/trans i have sitting.

The 96 is still a 3 wire pin connector, but the plastic body is longer.