Hitachi final drive motor destroyed how to get the pistons out

Hi Guys well I have pulled the final drive motor off that wasn't working and now we know why it destroyed itself , I am trying to work out how it comes apart , on the body so I can take the pistons out anyone have any ideas its a Hitachi 60 urg 6 tonner 1995 model see the picture of what I am trying to remove its the piston body and pistons any idea appreciated regards Tom