Definitely suggests that it's not the CPS itself.

Looks like the difference between the Auto and manual part is clear in the connector. Auto is circle, Manual more of an oval. In other words, you couldn't plug it in if was the wrong part. They are definitely different parts though.

I'm not sure what you mean by "OEM is an issue it seems". If you mean "finding one for sale for a 31 year old vehicle" then yes, that's for sure.

How close are you to north central MA?? I have a known good CPS in my 95 that according to RockAuto would work for you but I'm far too lazy to pull it and ship it myself and I'd bet dollars to doughnuts that it wouldn't solve your problem.