No being judgy, but the APCs I recall seeing sometimes were full of kit and it was hard to shove troops in between the rucks, piles of ammo cans, jars of Cheez Whiz and palettes of bottled water.
I wonder how many you could pack in there if you just had fighting order, first line ammo, CSupps and weapons, and backloaded all the other gear (except the Cheez Whiz of course) to A/B Ech etc..