This article is from the Ducatis Motorcycles FAQ, by Duke Robillard duke@io.com with numerous contributions by others.
Basically, you drive it out from the WHEEL side of the caliper using a
punch. It has a spring collett on the outer end that fits into a recess on
the caliper. Looks kinda like this:
/ \
===| |============= < drive it out from the INSIDE
===| |=============
\ / PIN
COLLETT
 
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