Last night I cleaned my exhaust joints and reattached, paying close attention to fit. I added muffler sealant too.? Checked and no leaks that I could find this am.
Went for a drive and my idle stumble is still there...
This may be a feature not a bug and I have spent WAY too many hours chasing it. No CELs and the van gets solid gas mileage and runs great overall. Not much to complain about.
If something else shows up I will post it, but otherwise I need to move on with my life on this particular issue. Thanks to everyone who has contributed, it helped immensely knowing there were some folks interested and available.