My welding is pretty poor so I thought I might just manage this by cutting through the flanged retainer and using this on the spring about half way down. I held it clamped in the vice to avoid the whole thing exploding across my bench.
When I fitted the spring retainer I was very careful to use pliers and not get my fingers (or anything else) too close.
It all worked a treat although as the springs were a little on the long side it was hard work compressing them.
