Managed to inch (that's an exaggeration) mine out by levering under the casting where the bolts go through. Having a jack underneath and lifting the weight of the vehicle helped.
Took a couple of hours using pinchbars, steel packing etc. etc.
Problem seem to be caused by dirt/water getting in the top but the tight fit of the lower collar keeps it there. greasing it when you put it back will give the dirt something to stick to so I'm not sure it will make it easier to get out in future.
I've considered grinding a couple of slots in the lower collar or alternatively a large O-ring around the top to stop the water/dirt getting in. Thing is if I just put the overhauled one back it will outlive me anyway.....
http://www.aulro.com/afvb/series-ii-...rmobile-5.html
Overhaul including making the spring compressor here http://www.aulro.com/afvb/other-powe...ml#post1923438
Colin

