Minnflyer says:
I really don't even do it that way, it's just what is SAID to be the correct way. I put the brass sleve in from the top, and tighten the screw until snug.
Actually, there is a reason why SOP is to put the grommet in from the bottom: the flared end of the grommet gives a large area to bear against the wood, whereas when the grommet is inserted from the top, the small end has minimal area and can penetrate the wood of the servo rail when the screw is tightened.
Still, you can get by with doing things wrong, but that is not necessarily right. There is so much that can go awry with the aircraft that we need to remove as many negative variables from the equation as possible.
FWIW...