The tool kit for the early hubs consisted of some large hollow spacers and a QR skewer. I've never had to do it myself, and only half watched someone else do it one time.
For the rear hub anyway I think the large spacer/end cap went over the FW threading, and a QR was put through the whole assembly. As you tightened the QR it pushed/pulled the whole assembly through to the drive side. I do not recall if this was done with the end caps in place, or if they even come off like the later hubs.
For some reason I think the models that come apart like that actually have two different sized bearings, maybe larger on the driveside? That could also be completely wrong. No idea about the front hub.