So I got stuck. Royally stuck.
Blamed it on the CAD. Turns out I owe it an apology.
My case isn't shifting into 4x4. It is adjusted properly (linkage) and goes into low range as it should, just no front output drive.
I put the front end up on stands and with the lever in 4hi, I can turn the tires and watch the front d/s spin.
Argh!
Removal of the vacuum switch at the back lets me feel the shift rod moving properly, moves as if it is shifting into 4x4, but no front drive.
Any suggestions to my WTF situation? Definately something internal as I did shim the CAD fork and observed the front driveshaft spinning with the CAD fork and plate removed.