Dash Radio Replacement Kenwood KDC-115S
Since I was unable to get a definitive answer to this question I thought I'd post the scenario here and maybe save someone else the research time.
My Kenwood KDC-115S dash radio display had grown so dim as to be useless. I sent it off to Kenwood for repair and it was damaged in shipment to the point that I had to replace the radio. Unfortunately, the KDC-115S is no longer available.
I did not want to fool with rewiring the harness or change the mounting sleeve if it could be avoided. Since it turned out that no one, including those I talked to at Kenwood, could say that a particular radio was 100% certain to be 100% compatible with the KDC-115S, I ordered the Kenwood KDC-138/CR on a leap of faith.
It arrived today. After comparing the wiring harness color coding I plugged it in to the original plug, slipped it into the original sleeve and powered it up. Worked like a champ, delivering audio to all of the coach's speakers and to the original point, I can now see what station it's tuned to.
Hope it saves someone time in the future.
Dave & Cathy, 2002 Country Coach Affinity, 42', #6103, CAT C12, Sold - Retired From RV'ing, Linux Mint