I first placed a couple of pieces of our old quartz backsplash (from our DIY kitchen backsplash project) on top of the hearth to get a basic idea of where the mantel had to sit. I’m glad I saved those!
Then I ripped off the old mantel. Easier said that done! I didn’t want to damage the TV or sound bar above it so I didn’t just go willy nilly on the thing. I ended up completely dismantling (no pun intended!) the mantel with a reciprocating saw and a 12″ construction blade that cuts through metal. It was actually super hard, which in fact the entire thing was held to the wall with a few nails and caulk. Sigh. Underneath the mantel were a couple of boards screwed into studs.