Black Cap Basslet with Royal Gramma

[Treebeard]

My Royal Gramma passed on a few weeks ago from old age I assume. She was one of the first fish we added to our first tank 5 years ago and a favorite. I am thinking of adding a Black Cap Basslet and wondering if I could also keep a Royal Gramma? From what I have researched, they may not get along, but others have suggested if they are introduced at the same time they may be OK. Anyone had any success keeping them together?