A check engine light for oil pressure? And just what DTC would that be?

I've driven three Crossfires a total of 80,000 miles and I am quite certain our cars were built without any monitoring of oil pressure what so ever.

I could be wrong, but I don't think I am. Idling oil pressure with 0W40 at operating temperature is specified to be "at least 3 pounds". That means you'd get no indication of low oil pressure until you have no flow at all - there would be no warning what so ever. (In the 1970's I know that the oil light came on in the Pontiac 350 V8 at 10-12 pounds, but we all ran 20 or 30 weight oils back then.)

This is why my cars get an oil pressure gauge!