Brainstorm's head would pop up in back where is head normally is in robot mode. Weirdwolf's robot head would be like Slag, open the wolf mouth totally and have the head inside. Mindwipe's head would be the back of the bat head, I guess like Kickback, and the small point of the bat head would make him a smaller cone-head like the Seekers. Not sure how they'd do Skullcruncher, but I would have liked it if the alligator head became his arms. Non-opening mouth of course, the alligator head would split in the middle and move to the sides and you'd add fists on them like the Seekers.