Top-to-bottom modernization and build-out projects worth about $7 million are under way at Deaconess Medical Center as the South Hill complex readies more space for Rockwood Clinic doctors and staff. In the basement of the Deaconess Health and Education Center, a 13,880-pound, $1.5 million MRI unit has replaced a smaller, less-powerful unit, Chief Operating Officer Greg Repetti said. Getting the smaller machine out and the larger unit in entailed the temporary removal of a portion of foundation wall, work that has blocked Fifth Avenue.