I just drilled and tapped mine to 6mm and took them out with a sliding hammer then just put the new ones in with a punch.
ftp://host217-41-52-224.in-addr.btopenworld.com/array1/share/Renault/Disc%202/dialogys/data/mrnt/en/nt/big/NT6000/6027A.pdf copy and paste this and if it opens ok for you it will tell you all you need to no.