Dear John
to which BOMBOS version do you refer? The use of BOMBOS can help; if indication of use of BOMBOS is based on questions coming up in this FORUM then it is used rarely.
C.B.
PS: the topic you have raised is "real" live. And therefore by using SAP EHS you will find a solution. If the solution can be handled "simply" is a different topic (an it is quite common to have at least two BOMs per Plant)