Greg, I had an experience pretty much the opposite of yours. I had a washed out 5CP head. They told me if it was a "W" head it would be warrantied. I told them it was, since it had "W-1" cast right into the head. They said, no that's not a "W" head and won't be warrantied. I asked WTH was a "W" head if mine wasn't. I basically got talk in circles, and told that it must have "W" stamped in the front and not cast into the head. Long story short, they wouldn't budge. To add insult to injury, they SOLD me a warranty replacement "R" stamped head, which does not carry that lifetime warranty. That was almost 20 years ago...I haven't forgotten.
To date, I have 30 HP pumps. Of those, there are only two Cats that were on used equipment that I bought in 2016.