sounds like a BOM (Bill Of Materials) set of tables to me. Each assembly is made up of some group or package, which in turn are made up of parts. However, the complexity can be high, as in assembly of multiple sub assemblies then Compoment(s) then Parts per component or just assembly > component > parts
You'd decide on how many levels you need, and each level is a junction table with each record being a child of that particular level. So maybe research BOM databases.
You might find a schema for this here
http://www.databaseanswers.org/data_models/
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.