I've drawn a part (picture 1) that I plan on machining multiples of in a vice. I have machined the fixture with locator pins but I'm struggling to figure out how to add the parts with their associated stock material into my assembly. When I add the part to the assembly (picture 2), it obviously just shows the part and not the surrounding stock material. In order for my fixture and the corresponding machine ops to work, I need the parts to be inserted with their stock material. 

One more thing to think about is my second op. I will be using the same fixture and flipping the parts over for the second op to face the back side of the parts. I have created a second assembly (picture 3) with the parts flipped in that direction but I'm up against the same problem as far as showing the stock material. This op will be unique as well because half of the stock material will be gone (picture 4 and 5). I've seen some stuff about using WIP but have never actually used that. 

Any help is always appreciated.