Hexagon productions PPSH-41 assembly

[bulletman]

Hi can someone help me please ,my ppsh-41 had a problem of not cycling so I decided to take the gearbox out and see what the problem was, anyway found out it was the motor wire had snapped repaired it .Now the problem I have is trying to reassembe the damn thing any body ever done one before also I don't know if I've lost a screw, when I do get it all lined up when I tighten it the gearbox is still loose and also there is a black thick piece of rubber and I haven't got a clue where it go's ,any help would be most grateful.