Hey, I have the same problem with my '73 Travelall 1110. I can pull the axle out as far as it'll go (or use leverage on the u-joint)and still not even close enough to even see the groove that the retaining ring should set in.
Is it possible there's something else going on, like inner/outer spindle locknuts or the washer between them with the holes is causing this?
Btw - I took off the outer spindle nut and slid the warn hub in place and the shaft still does not stick out far enough.
In case mm sees this, this is the t'all you looked at for me last yr and I am referring to that warn hub intended to replace the old Ford one that the po put on the psgr side that needed replacement....
Note that I looked online and found this tidbit on a warn 9790 pdf file (it might indicate that it is acceptable to not install the ring?):
step 8. Install the axle retaining ring. If necessary, a pry bar can be inserted into the knuckle (universal joint) to hold the axle shaft outboard while installing the axle retaining ring.
Note: some early model solid front axle May not accept axle retaining rings (77 ½-79 Ford’s, 81-84 and some 85 Chevy/gmc’s). Use them if they can be installed correctly (outboard of the hub body) but their use is not mandatory and no durability loss will be suffered. All fords with twin traction beam front axles (independent front suspensions) must have an axle retaining ring installed.