just to add my bit....... i could not get the drop arm off of my 90 steering box, puller, hammer, swearing, would not move, but i guess they must come off. In the end I went for a replacement steering box, as i was informed by far too many people that the seal would only go again once fixed anyhow.
I did buy a seal kit for the 90, and i may still have it in the garage, not sure if it will be any good to you, but if you are interested PM me and i will post it to you if i still have it.
Andy