2005 Boards member pokemonsdoom brought our attention to a small detail in the instructions of the Japanese Takara Tomy release of Studio Series Scrapmetal.
There’s an indication on where to attach Scrapmetal’s small shield piece (made of a panel from the excavator mode) in his combiner mode. Scrapmetal forms the left hand/claw of Devastator and according to the extra image on the Japanese instructions, you just have to connect the shield on one of the “fingers” in this mode. Hasbro instructions didn’t mention what to do with this shield, leaving it up to you.
Takara Tomy Website has also uploaded a pdf file of the instructions, so you can check it out (61 megs file, though). Alternatively, click on the bar to see the mirrored images on this news post.