HELP with engine vacuum hose for 420SEL

One of the vacuum hoses in the engine bay has come loose and i do not see where it connects. Does anyone have a diagram of the vac system in the engine comp? the hose is located on a pipe looking thing that comes off of the headers, if you open the hood is located to the right headers. Please help car runs fine,but from time to time seems to shake a little (Rough Idle). Thanx