Jack,
Does the foam square go behind the air outlet grille? When I stripped my 1124A down, I don't remember coming across a similar part, so if not, might it fit between the motor and bag/handle assembly?
Your doing well with all that foam rubber intact by the way, on both my Convertibles it's disintegrated into crumbly mush.
Are the missing screws for the metal bracket on the belt side or the plastic one by the dirt duct? I can pop mine off my cleaner tomorrow to see if I've got any suitable spare ones for you!
Si