@Updraft: I understand what you are saying and I do structure my assemblies by the correct configs, this example however is a little unique. The part that I am talking about is only modified at the top level assembly each time. Imagine building up a car. The part in our example whose config i want to change is (for example) the wheel. The tire gets put on the wheel and that is a subassembly. Then the tire/wheel subassembly gets put on the frame which is another subaseembly, then so on and so forth until we have a complete car. Then at this point, once the car is done, I drill holes in the wheel. But I only drill holes in the wheel once the car is done. So I have a wheel with a drilled and non-drilled config. But I need to carry the two configs all the way up through the assembly (through several subassemblies) for me to be able to configure the assy with drilled and nondrilled wheel(I understand I can drill holes in the assembly and make a config out of this, but the config that I need is not as easy as drilling holes/adding a feature). I hope this makes sense. After writing this I guess I could just have a second part (wheel) model that I add at the top level assembly which I could configure..