Absolutely, you can mount a full-sized PiBow or a PiBow Coupé to the spacers of the LCD screen driver board using the supplied bolts through the 4 HAT mounting holes on the bottom layer of the PiBow.
You have to bolt on the bottom layer, and then carefully build the rest of the PiBow up around it. I do this by pushing the screws through from the bottom layer, facing outwards so they're easier to bolt on afterwards.
Edit: Added hastily taken picture for illustration:
You can feed the ribbon cable through the top layer before you put it into place:
