I have a single pull/push bath handle, I need to replace the cartridge inside, problem is I cannot figure out how the handle is attached to the fixture. It appears the handle is one solid piece of metal. I can not find any set screws holding on the handle. The handle is simply a round piece of metal with grooves on it. I think it's a Moen faucet.
Attached are a couple of pictures. The spot on the front is where I started to drill through cap, not plastic, solid metal. The white plastic piece in the back seems to be attached to handle. All around the handle is the same no set screws are visible.