by bdring » Wed Feb 13, 2013 1:44 pm
Just push the nuts out using a vise or drill press. The inserts are really tough, but you need to be careful about the plastic part. You can push on an M8 bolt threaded into the insert or use shank of a drill bit slightly larger than 8mm.
I would try to use the existing part rather than print one. If it is not smooth, flat and square it defeats the purpose of isolating movement on the shafts.
Bart
"If you didn't build it, you will never own it."