This is a spiffy build, but it has caused me to ponder a bit.
The Combat Car, 6x6, M-8 was the "Greyhound" but did the Combat Car, 6x6, M-20 ever get a proper nickname?
Soldiers being soldiers, they probably called them [expletive] at one time or another, but must military things will get such pithy and unprintable monikers.