Definitely no observable looseness (in/out) in the unlocked position at least so far. Everything is still stiff, new, and somewhat cold in my garage but the unlock position has sort of a detent on the back side of the actuator knob and it seems to sort of snap into the unlocked position thanks to that detent.
I would expect any looseness in the actuator knob to occur in the locked position since the spring that causes the engagement doesn't really seem very strong. I wonder if a Warn spring would be stiffer. Again, no looseness yet but as soon as I get it drivable again, I'll take it out for a spin and get everything warmed up. Breaking in the new BMB brake pads should get everything nicely heated up if the weather isn't too cold. Then I can check everything carefully again.
For anyone interested, this is a Reid knuckle, 5x5.5 locking hub conversion. I got the knuckles from
@mattcogdell. And the big brake kit came from
@mrblaine at Black Magic Brakes. So thanks to both of those guys! The setup uses a mid-seventies 4x4 spindle, stub shaft, etc. To get the 5x5.5 lug pattern, I'm using a Ford hub. BMB supplied the calipers, pads, rotors and all the bits needed to mount it up to the knuckle/spindle.
The knuckles are not being produced any longer so this is not a viable option for most.