I have no idea about "Centric" but I used a kit from these guys years ago https://secure.amesperf.com/qilan/Search_Web?order_number_e=NTI0MTU4NA%3D%3D%0D%0A&method_1=&method_2=Y&on=Y&search_method=2&cat_rowid=2 and no you never use grease inside of the brake Hydraulic system or you will contaminate and ruin all of your hydraulic parts. Instead of me going step by step through the proper steps I suggest you just look up how to rebuild a caliper because even though the hard parts are slightly different the procedure itself is exactly the same. Also a bit of advice, after your done depending on your budget this fall after cruising season is over the best thing you can do is send them both off to one of the rebuilders who install the stainless sleeves in the bores. Good luck.