I remember doin this Mike, I ended up knocking the splined portion out of its socket and using it on its own with a spanner to turn it, gave just enough room
Cant get the splined section out the socket Ive got now. But I did manage to get a 12mm spanner on some of the spline, wasnt enough leverage, or I am a pussy
Had a word with DaveB, turns out it is a swine of a thing to do. He recommended what I'd thought might be a bit daunting and unbolting the arm & bottom of the shocker giving more room....
I might have a go at getting the splined bit out and finding a longer spanner...
Thanks Gaz