Need to remove the 2 7mm screws from the calipers. Problem after that is that you will need a special tool to push the pistons in. The pistons need to be turned clockwise kiinda like screwing them back inside but you also would need to be bushing in as you turn. You can try some long needle nose pliers but it is going to take a great deal of effort from you to hold the caliper, push piston in and turn all at same time. Good luck.