the t case shifts nicely from hi-n-lo
Good
4wd-2wd clicks smooth as butter.
Good
the 2wd-4wd pulls back into 4wd and stays but dosnt click.
This is also good. There is no click or transition between the passenger's side 2WD/4WD shift rail and the driver's side Low/Neutral/High shift rail. The shifter simple tilts to the right (to operate L/N/H) or tilts to the left (to operate H/N/L).
As for with or without an interlock pin, there is no immediate operational difference between the two, and all of the factory shift "clicks" will function the same. The only difference would be if you were to somehow very quickly engage from 4WD-Netural into 4WD-High really really fast while apply a lot of pressure towards the driver, and you might be able to get the shifter to fall into the 4WD-High slot while the left-side shift rail returns back into the Neutral position (effectively locking you into neutral).
The only other issue would be if you drove straight into a brick wall at a high rate of speed, and depending on which transfer case position you are in and if you are driving forward into the wall or reversing, you will cause the free shift rail to shift on its own also locking you into whatever t/case position you happened to be in. But in this scenario you'd have a lot more to worry about then a stuck t/case
Regards,
BigMike