Nick,
The fact that a hub might have come loose in the past, is worrying. I used to work on these when they were in Army service, and if a hub was not tight on the taper it would then put load on the key and keyways, and also wear the tapers so that it was not possible for the hub to fit tight again. You can sometimes hear a creaking noise if a hub is not tight. As for pulling the hub off, if it is fitted tight, then only puller to use is the proper one, which resembles the hub cap, but with a gurt big screw in the centre. You used the hub nut slogging spanner to load this screw and hopefully release the hub.
Richard