I tried for a long while to undo the cartridge, HOLY CRAP these are tight. Matt thanks again for sending me the template, unfortunately it was different to what I needed, my spring land only has 4 posts:
I made my own tool with PVC pipe but it's too weak to lock the cartridge to undo it. Half heartedly tried a few different things, along with heat but ultimately I failed to get the cartridge undone. I've made up a template so I can make something up out of metal which should be strong enough.
Next problem is the best way to undo the bottom of the cartridge when it is locked. How is this done? I'm tempted to stick a bit of 6mm rod through the oil holes in the bottom of the damper tube and use that to undo the tube from the spring land? Is this safe to do?