my friend was trying to replace a brake line and broke off the banjo bolt in his caliper and now he needs to drill it out. but the piston is in the way of the other side of it. so can anybody tell me how to get the piston out? this is with a type R brake setup by the way

 

you need to by a rebuild kit with new seals and such but just stick a piece of wood in front of the piston and blow compressed air through the back and it should shoot out