When I changed the rear springs, I made sure that they were well lubricated - sitting on the bench overnight with oil sitting in the grooves and the centre bolt slackened. Night 1 one way, then night 2 the other way. Then I wrapped them in Denso tape.
Good old Denso tape. Wrapped the Series One springs over 20 years ago in Denso. Took it off one of the springs a couple of years a go to check the condition of the spring, Glad to say it was in perfect condition and that's after quite a bit of off road driving.
