Hi
I have absolutely no idea whether this is possible, just a logical thought.
Can you do nested BOM's?
BOM1 = all components needed for both items.
Then BOM2a contains BOM1 + the custom items for one variant.
BOM2b contains BOM1 + the custom items for the other variant.
I am interested in this as it is an area I need to look into in the near future for a client.
Cheers
Heather