The Energon Pub

I know IDW has shown us a bit what Metroplex looks like on the inside in city mode, but not much. Are there any other media showing us what the other citybots look like on the inside, whether comics or cartoons? I got a glimpse of Trypticon's insides in the Animated cartoon/comic where he was a prison for the elite guard, IIRC, but that's about it. I'm probably missing out on some neat art showing them off, but I haven't seen any other media depicting the insides of citybots.

I believe the G1 S3 episode "The Ultimate Weapon" (a personal fav thanks to First Aid and The Netherlands being featured.) has some shots of inside Metroplex and Trypticon, since a side-plot involves their Transformation Cogs.

Good call on "Ultimate Weapon". The Return of Optimus Prime Pt1, also has a medbay (presumably) inside Metroplex, as this is where Rodimus takes the non-functioning Optimus, meets Wreckgar, then proceeds to "shut down" Metroplex to avoid him catching the hate plague.

With regular TFs, most of their internal cavities would be used for transformation movements. With city-formers, some cavities would have to be kept untouched and unused during transformation because those are occupied by TFs and their equipment and possessions. These cavities are commonly known as 'rooms'.