Lying in bed this morning getting over the flu and reading this thread again I remembered I had some new unopened nolathane strut top bushes/bearings in the shed and I also kept the originals from when I did my suspension. So getting ever more bored I decided to open it up and check one against the other. All overall dimensions, apart from the sagging, were within a mm or so of each other even though the old ones are pretty rooted. The thing that was blindingly obvious though was the difference in the washers supplied with the nolathane ones. I painted the original one with white texta so you could see it better. Overall the original is 7mm thick and the nolathane one is 11mm thick. I think these washers should be underneath the bush and reuse originals on top? Don't know if its that simple but I hope this solves your problem.