Pianotech

I will be installing dags/dogs/keyboard-holdy-downy things on a Steinway L.  Does anyone know of a reference to how much clearance there should be for those blocks?  My initial thought was maybe +.006" (two pieces of paper), but I wanted to check if anyone had experience with needing more/less clearance.  I will be making the blocks myself.

My searches through my own resources have not turned up anything yet.

Thanks in advance!