guess you could use any shuttlecraft as an analogue.
I'd say the shuttles are a different beast altogether: their balance of low performance and high cargo capacity results in a very different vehicle where the components might be inherently easier to hide. Think delivery van vs. racing car, or delivery van vs. recce-configured APC.
Just like T'Girl
sez, a volume marked in those blueprints is probably cramped beyond its seeming dimensions because it is actually full of stuff...