FYI, I just spent all of yesterday freeing up both motors which were completely seized due to non-use for the entire life of the vehicle up to 70,00 miles, completely resealing my actuator(the two shaft seals + the big o-ring) and re-timing all the gears. The actuator works flawlessly, as far as I can tell there is no axial load on the shift shafts when fully engaged in either direction. The diff locks/unlocks in ~2-3 seconds and the 4 hi/low engages/disengages in about the same period of time.
It's a painstaking process, it took me a week to find the seals and get them in the mail, and about 6 hours to remove, repair, and reassemble everything. The hardest part was protecting the shaft seals from the sharp stepped edges on the shafts (where the teeth end and it steps up to a smooth sealing surface). I ended up coating the shafts with grease, wrapping black electrical tape around each step 1.1 times (and then leaving a "tail" of tape hanging down from each shaft), sliding the actuator on, then pulling on the tape causing it to stretch, slide around the shaft, and come out, leaving nothing but a little grease behind.
Everything is good so far, no leaks inside the actuator nor outside of it, and I can now engage that handy center diff next month when silver lake sand dunes open!
I took a bunch of pics. I think it might be good to do a write up on this and explain how i did it. I used a 12V/1A battery charger to run the motors, this was the only way I could get the unit off the transfer case without splitting that stupid case. Removing it with a seized motor is easy because you can remove the cover and then pull the shaft which 2 of the gears ride on - This lets everything spin freely even with a seized motor.
I am so happy it worked, just about as happy as I was pissed when I found out how much the actuator cost and how much work I had to do in order to install it...