I bought a house that has cinder block wall in the backyard. Whoever installed this wall opted to place the top blocks so that the holes are facing the side rather than the top and bottom. They then covered the holes with ceramic tiles. From what I can tell, those tiles were attached using some kind of grout or caulk. I'm not really sure, but I can the tiles were about ready to fall off anyway because most of them popped right off without much effort. I'm trying to make this look bettee, so I'm going to paint the wall with masonry paint and put new porcelain tiles up to cover the holes.

What is the best strategy for attaching the porcelain tiles to the painted wall? I'll be using 6 inch tiles (same size that were previously installed).

Here is image of what I'm working with: