Heres my method I cut and pasted from removing the m900 inserts this summer. Needless to say I needed to not have bothered at all because powdercoating wouldn't have affected them and they were not worn.
" After the epic FAIL in even getting 1 cush drive out yesterday and drilling the centres out after giving up. I cleared the rubber out as good as possible and tried the dremel attack but wasn't getting very far and ended up pushing one further down.
Got my engineering head on and watched a video and couldn't quite see how he was getting them out but I realised that there is a gap about 8mm at the bottom. If I could somehow get something to expand under and slidehammer it would be easy. I did think about making a tool but that's madness when you want them out now but if the idea helps others I am happy.
I got a long M10 bolt so the head would sit under the bottom of the cush drive. 2 side by side would fit so I needed something to pack the difference and used a socket and then retained it with a couple of strong washers and a nut. With that holding firm I could then attack from the rear through the disc brake side and had a nice surface area to tap through. A few sharp drifts and they all came out and they annoyingly were clean as a whistle but I had to finish the first one with a hacksaw and gradually lever it out. Some minor damage will clean up ok but finally they can be get given to specialists to apply a good finish.
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